The SDA church is Gods Remnant Church of Revelation

Here is a excellent explanation in the article 'The Remnant of God, or Spiritual Israel at the End Times' by Professor Walter J. Veith from Amazing Discoveries:

Throughout the ages, God has had a people through whom He chose to disseminate His truth. It was God's plan that all people - every nation, tribe and tongue should become partakers of His grace. In His divine plan of restoration, He chose fallen human beings to become co-workers together with Him to achieve this end. God has always had faithful followers who would stand for truth and justice even in the face of great opposition. Before the flood, Enoch walked with God, and faithful Noah became the father of the post-flood human race, when he and his family were the only remnant to be saved from the destruction of the then-time apostate world.

After the flood, the patriarch Abraham was given the promise that through his seed all peoples would be blessed.(Genesis 12:2) The Messianic promise was to be realized through Isaac and Jacob whose name was changed to Israel after he wrestled with God for divine forgiveness and blessing.(Genesis 32:28)“Israel” became the name of the descendants of Jacob - the chosen people in terms of the covenant between God and Abraham their forefather.(Genesis 15:18; Psalm 105:9,10)

First lets go through the Isreal of God in Old Covenant Israel.There is much confusion today as to who constitutes the Israel of God. Many denominations seek the fulfillment of the promises of God to ancient Israel in modern Israel. They expect the restoration of Israel, and the modern Israel in Palestine is seen to be integral in this process. It must be remembered that “Israel” is not the natural name of Jacob, but was given to him by God in recognition of a spiritual victory when he prevailed with God and secured pardon for his past sins. Jacob wrestled with the Angel and refused to let Him go unless he obtained the surety of the heavenly blessing which would grant him the pardon of his sins. Jacob prevailed and received the blessing, his was heart was renewed and he could face his brother Esau knowing that God was with him. The name change signified a change in character from the “supplanter or deceiver” to “God contends”. An understanding of the relationship between physical Israel and the covenant people of God is vital if we are to discern who God’s light-bearers are in this modern age.

Following the Exodus from Egypt, God formally entered into a covenant with the nation of Israel.(Exodus 19:1-8) Israel was to be a kingdom of priests and a holy nation (Exodus 19:6) and they were to spread light to all people on the face of the earth.(Isaiah 60:1-3) The covenant promises made to ancient Israel were conditional to obedience.
Now therefore, if ye will obey My voice indeed and keep My covenant, then ye shall be a special treasure unto Me above all people; for all the earth is Mine. Exodus 19:5

The promises were subject to "if". The physical throne of Israel was always conditional to obedience, and both David and Solomon were informed on this issue.
...that the Lord may continue His word which He spake concerning me, saying,"If thy children take heed to their way, to walk before Me in truth with all their heart and with all their soul," He said,"there shall not fail thee a man on the throne of Israel."1 Kings 2:4

This promise was repeated in 1 Kings 9:5-7:
...then I will establish the throne of thy kingdom upon Israel forever, as I promised to David thy father, saying "There shall not fail thee a man on the throne of Israel." But if ye shall at all turn from following Me, ye and your children, and will not keep My commandments and My statues which I have set before you, but go and serve other gods and worship them, then I will cut off Israel out of the land which I have given them; and this house which I have hallowed for My name I will cast out of My sight. Israel shall be a proverb and a byword among all peoples. 1 Kings 9:5-7

Deuteronomy 28:1-14 contains a list of the most wonderful blessings ever pronounced to any nation or people. Again the promises were conditional to obedience.
And all these blessings shall come on thee, and overtake thee, if thou shalt hearken unto the voice of the LORD thy God. Deuteronomy 28:2

Israel did, however, not heed this admonition and became more corrupt than the nations around them.(2 Kings 17:6-23) Only the tribes of Judah and Benjamin were spared for a while, and the other tribes were carried away captive by the king of Assyria and disappear from history, though some believe that they constitute the nations of Britain and their descendants including the USA. Without loyalty to God, the promises could not be fulfilled, and a century and a half later, even Judah was plucked up from the Promised Land and scattered in the Neo-Babylonian Empire.

Nevertheless, some had remained faithful to God even in the face of this calamity as is shown by the stories of Daniel and his friends who were willing to rather face death than to disobey God. Through the prophet Jeremiah, God had granted a specific time for repentance and reflection, and He had promised that they would return to their land after 70 years of exile (Jeremiah 31:10-14; Isaiah 43:1-13). They were to rebuild the temple, the time prophecies of Daniel predicted the advent of the Messiah; and they had the opportunity to be witnesses to the nations (Micah 4:1-4; 5:2-6; Zechariah 8:20-23). Again all these promises were conditional to obedience (Zechariah 6:15). Sadly, the nation rejected the Messiah, and forfeited its covenant role and the covenant promises. By Rejecting Jesus, the house of Israel became desolate.
O Jerusalem, Jerusalem, thou that killest the prophets, and stonest them which are sent unto thee, how often would I have gathered thy children together, even as a hen gathereth her chickens under her wings, and ye would not! Behold, your house is left unto you desolate. For I say unto you, Ye shall not see me henceforth, till ye shall say, Blessed is he that cometh in the name of the Lord. Matthew 23:37–39

Now lets go through the Isreal of God in New Covenant Israel. When the Jewish nation rejected the Messiah, the gospel was to go to the Gentiles and all who would believe in the name of Jesus would become the spiritual descendants of Abraham.(Galatians 3:16; Romans 4:16; Romans 9:3,8)
And if ye be Christ’s, then ye are Abraham’s seed, and heirs according to the promise. Galatians 3:29
The apostle Paul speaks of Christians as the “Israel of God”(Galatians 6:16) and the “circumcision”(Phil. 3:3) The kingdom of God and the covenant promises associated with it were to be taken from the Jews and passed on to spiritual Israel - those who would permit Christ to transform them, to change their character as was the case with Jacob of old.
Therefore I say to you, the kingdom of God shall be taken from you and given to a nation bearing forth the fruits of it. And whoever shall fall on this stone shall be broken; but on whomever it shall fall, it will grind him to powder. Matthew 21:43,44

Jesus did not choose 12 disciples coincidentally. Just as the twelve patriarchs were the founders of ancient Israel, so these twelve men are the foundation stones of new Israel to which the Lord promised the kingdom (Matt 19:28; Luke 22:30). The subsequent choice of seventy others is modeled after the choice of seventy elders by Moses in ancient Israel (Num 11:16). The real Israel of God is a remnant chosen by grace (Rom 11:5). There is a marvelous continuity between the old and the new Israel of God. In Romans 11:17-24, Paul speaks of the olive tree which represents Israel. The branches (Jews) were broken off because of unbelief and the wild olive shoots (Gentiles) were grafted in to share in the nourishment of the tree. The natural branches could be grafted back into the tree if they accepted the conditions. God is no respecter of nations or individuals. All who turn to Him will be accepted (Acts 10:34,35).
For there is no difference between Jew and Greek, for the same Lord over all is rich to all that call upon Him. Romans 10:12 NIV.
For ye are all the children of God by faith in Christ Jesus. Galatians 3:26

The new Israel is the inheritor of God’s covenant promises. Those who have accepted Christ have become the chosen people, a royal priesthood, a holy nation, a people belonging to God.(Compare 1 Peter 2:9,10 with Exodus 19:5,6) They were chosen to reveal God’s marvelous light to the world,(1 Peter 2:9; Matthew 28:19,20; Ephesians 3:10) a remnant, called out to shine the light of truth and prophecy of the end times, and are those that keep the commandments of God and the faith of Jesus.

The human race is in desperate need of redemption, yet many reject his commandments and the faith of Jesus. God yearns to forgive and cleanse and never gives up trying.(John 3:16; 1 Timothy 2:4) Henceforth it is the role of the remnant or Spiritual Israel to carry Gods truth to the world.

Two of the identifying marks of the remnant listed in Revelation 12:17 are that they "keep the commandments of God" and have the "testimony of Jesus". The "commandments of God" refer to the Ten Commandments, which includes the fourth commandment regarding the seventh-day Sabbath. Also, Revelation 19:10 equates "the testimony of Jesus" to the "Spirit of prophecy", which Adventists believe is a reference to the ministry and writings of Ellen G. White.

Adventist scholar Ángel Manuel Rodríguez, has observed how some view the concept of the 'remnant' in the present day church:

"it is with great concern that some observe a tendency to de-emphasize or ignore this fundamental self-definition [of Adventists being the remnant]". Rodríguez identifies six different interpretations of the "remnant" that have gained popularity within contemporary Adventism:
The traditional position — The remnant is equivalent to the Seventh-day Adventist denomination.
The remnant includes Adventists and non-Adventists — Although the Adventist church bears the unique "remnant message", all faithful and sincere Christians (regardless of denomination) can be counted as being among the remnant.
A remnant within the remnant — Only a select group within the Adventist church constitute the true remnant. The church as a whole is in fact headed into apostasy.(This view tends to be held by ultra-conservatives.)
The remnant is an invisible entity — In contrast to the traditional position, which defines the remnant as an institutional/ecclesiastical entity, this view regards the remnant as an invisible body which transcends the Adventist denomination. It is promoted by progressive Adventist Steve Daily.
The Remnant is not yet a Reality — The prophecy of Revelation 12:17 is as yet unfulfilled, and as such the existence of the remnant is still future. This position has been suggested by Jack W. Provonsha.
Sociological Understanding of the Remnant — The mission of the remnant is to work for social and political reform. The remnant should not be defined in exclusively religious terms.
http://www.adventistbiblicalresearch...tSDA church.htm

In his conclusion he states..." The different uses of the concept of the remnant in the Old Testament are useful in refining what we mean when we call ourselves the remnant church. We are the historical expression of the eschatological remnant, raised by the Lord after the fulfillment of the prophecy of the 1260 years recorded in Rev 12. The historical remnant is at the same time the faithful remnant in the sense that they are the bearers of God's message to the world. They have been entrusted with a mission and message from God that, if accepted by others, will be a protection against the last great deception of Satan. This is a visible remnant that can be identified through some specific marks. The fulfillment of their mission requires the presence of some type of organization, and the Adventist church is the only one that fits the description. The SDA church is the Remnant Church of Revelation which has all the attributes and from its conception has been entrusted with a mission and message from God for the End Times.

Castaway57 said:

So are you saying that these two "marks" are the only ones which would identify the remnant church?

I would agree that these two points are essential "marks" yet, it must be noted that these "marks" are often poorly understood, and many bad witnesses to these "marks" are given by people. Also, these two "marks" do not include other essential "marks" of the remnant church. For some reason; most prefer to only mention the Sabbath, and Ellen White when talking about characteristics of the remnant church. Should it be this way?

Click to expand...

Here is a great explanation..

The Lord has marked His remnant church. He has stamped upon it such indubitable recognition that none of His children can mistake it. God saw the necessity of placing upon His true people these two outstanding signs, for the Scriptures declare that in the last days Satan will work with all power, signs, and lying wonders, so that if it were possible he would deceive the very elect. Matt. 24 :24 ; 2 Thess. 2 :9, 10 ; Rev, 12 :12. That His chosen ones might be saved from the snares and deceptive power of the evil one, God has pointed out such distinct characteristics of His own true remnant church that the sincere, honest believers need not be misled. 2 Cor. 2:11; Eph. 4:14.
A firm belief in the commandments of God and the testimony of Jesus Christ are two outstanding characteristics of the remnant, the true church of Christ. That church which bears these marks is the church which will wait for the glorious appearing of the Lord. 1 Cor. 1:4-8; 1 Thess. 4:16, 17.
Within two months after the disappointment in October, 1844, the gift of prophecy was restored, and accepted by those believers who by faith had followed our great High Priest into the most holy place of the heavenly sanctuary, to conduct His final intercession for sinners. (See 1 Sam. 3:19-21.) In various parts of the field where the advent message had been proclaimed, there arose men and women who abandoned the observance of the first day of the week as a religious day of rest, and observed the seventh day of the week as the Sabbath of the Lord.
When the believers who followed their Lord into the most holy place in the heavenly sanctuary after the seventh month (October, 1844), saw in the heavenly temple the ark of God, they recognized that there was written on the stone tablets contained therein the command, "The seventh day is the Sabbath of the Lord thy God." This commandment had not been changed by divine authority. This law could not be changed. Ps. 89:34. The purpose of the Creator in originally giving the seventh day for the Sabbath was to memorialize the Creator’s works. In order that man might always acknowledge that this world was created in six days, God made the seventh day His Sabbath, His day of rest. There would have been no Sabbath had there been no creation. The seventh-day Sabbath can-not be dissociated from creation. They stand together. The world-wide message declares : "Worship Him that made heaven, and earth, and the sea, and the fountains of waters." Rev. 14:7.
To worship Him who made all things is to honor the day He made to memorialize creation. God used only six days in which to create. Whatever was essential for man’s welfare upon this earth, God made in those six days. There would have been only a six-day week, if God, through our Lord Jesus, had not established a memorial of His creation. The one and only reason the seventh day was made was so that as long as the earth existed God’s creatures might recognize and understand that He made this world and all in it in six days. With the observance of the seventh day of the week as the Sabbath of the Lord was joined the gift of prophecy. Those who accepted and obeyed God’s commandments, recognized the necessity of accepting the gift of prophecy. 2 Chron. 20:20.
When the people of God through the ages kept the commandments of God, they had entrusted to them the gift of prophecy. 2 Kings 17:13. The two always have been associated, and the Lord promised they would again be joined in the last days. The true remnant church would be recognized by those two significant divine marks. We have the remnant church located by the holy Scriptures.

http://gospel-herald.com/index.html

It is what it is.