Here are some quotes from a booklet titled
The Assurance, Security and Joy of Salvation - link at end - I hope they help you. 
"the Bible says it is possible to know absolutely, unreservedly, that you are a saved person. How can this be? Let us read 1 John 5:13:
I have written these things to you that you may know that you have eternal life, to you who believe into the name of the Son of God.
It is not, that you may
think, not, that you may
hope, but that you may
know. We do not need to wait until we die to find out; this assurance is for us to enjoy today.
How can we have the assurance of salvation? There are three means:
God Says So
Our first means of assurance of salvation is Gods Word. While mans word may be untrustworthy, Gods Word remains sure and steadfast. It is impossible for God to lie (Heb. 6:18; Num. 23:19). Whatever God says stands firm forever (Psa. 119:89).
What God has said is not a matter of conjecture. His Word is neither vague nor intangible. It comes to us today in written form, the Bible.
The Bible is Gods very Word, inspired by Him (2 Tim. 3:16). We can take this Word, believe this Word, and trust this Word.
What then does God say about salvation? He says that the way of salvation is a person, Jesus Christ (John 3:16; 14:6; Acts 10:43; 16:31). He says that whoever believes that Jesus Christ has risen from the dead and confesses with his mouth that Jesus is Lord is saved. He says that whoever calls upon the name of the Lord shall be saved (Rom. 10:9-13).
Have you done this? Have you believed in Christ and confessed openly that He is your Lord? Have you called on His name? If so, you are really saved. God says so. That settles it.
The Holy Spirit Bears Witness
Not only do we have Gods Word
outside us telling us we are saved, we also have a witness
inside us, telling us the very same thing. What the Bible speaks to us from without, the Spirit confirms within. First John 5:10 says, He who believes into the Son of God has the testimony in himself.
Sometimes, after we have received Christ, we may not
feel saved. Nevertheless, if we check within the deepest part of our being, with our spirit, we will find a kind of inner witness, an assurance, that we are children of God. The Spirit Himself witnesses with our spirit that we are children of God (Rom. 8:16). If you doubt that you have this inner witness of the Spirit, try this simple experiment: try declaring boldly, I am
not a child of God! You will find it very difficult to even whisper such a falsehood. Why? Because the Holy Spirit within you bears witness, You
are a child of God!
Our Love for the Brothers Is Proof
The third means of assurance is our love for other brothers and sisters in Christ. First John 3:14 says, We know that we have passed out of death into life because we love the brothers. A saved person undoubtedly senses a kind of love for others who are also saved. You sense a desire to fellowship, to enjoy Christ with others. This is the spontaneous result of being saved, one of the clearest signs of a saved person. This love transcends the cheap, selfish love of todays age. It is a love that is impartialit loves those who are alike and those who are different. This is the real oneness and harmony the world longs for. Yet it is ours when we receive Christ. How good and how pleasant it is for brothers to dwell in unity! (Psa. 133:1). This is the testimony of a saved person.
By these three witnessesGods Word, the Spirits inner witness, and our love for the brotherswe may know and be sure that we are really saved.
THE SECURITY OF SALVATION
After a Christian has received the assurance that he is really saved, he may consider, I know that I am saved today, but how do I know that I will be saved tomorrow? Is it possible for me to lose my salvation? For such a one, it is no longer a question of
assurance, but one of
security.
A man with millions in the bank has the
assurance that the riches are his. But if the bank insists on leaving their vault unlocked, our rich friend will have a real problem with the
security of his riches. He knows he is rich today, but he does not know about tomorrow.
Is our salvation like that? Is it something which we have today but may lose at any moment? The answer is, unequivocally, no. We can boldly say, I know that whatever God does, it will be forever (Eccl. 3:14).
One wonderful fact regarding our salvation in Christ is that it is irreversible, that is, it cannot be undone. Once we are saved, we are saved forever because our salvation has as its basis the very nature and person of God Himself.
Salvation Was Initiated by God
Jesus told His disciples, You did not choose Me, but I chose you (John 15:16). In other words, salvation was Gods idea, not ours. In eternity past we were chosen and even predestinated (marked out) by Him (Eph. 1:4-5). Furthermore, it was He who called us (Rom. 8:29-30). Since it was Gods plan to save us in the first place, it is also His plan to keep us in that salvation. Could God choose us, mark us out, call us into salvation and then abandon us? No, Gods salvation is eternal.
Gods Love and Grace Are Eternal
Furthermore, Gods love and grace toward us are not conditional or temporary. It was not love from our side that saved us, but love from His (1 John 4:10). He loved us with an eternal love (Jer. 31:3). His grace was toward us in eternity past, before the world began (2 Tim. 1:9). When Christ loves us, He loves us to the uttermost (John 13:1). No sin, failure, or weakness on our part can separate us from the love of God which is in Christ Jesus (Rom. 8:35-39).
God Is Righteous
But our salvation is based not only upon Gods love and grace, but even more upon Gods righteousness. Our God is a righteous God. Righteousness and justice are the foundation of His throne (Psa. 89:14). If God were to be unrighteous, His throne would lose its foundation. Therefore, if our salvation in any way involves Gods righteousness, it is very strong indeed.
Suppose you run a red light and are given a $25 ticket. That $25 fine is a righteous penalty, and the law of the land demands that you pay it. If a civil judge simply overlooks your offense and releases you without paying, he is an unrighteous judge. It is not a matter of whether or not the judge loves you; he is bound by the law to collect the fine.
In the same way, our problem before God before we were saved was a legal one. We had broken Gods law by our sin and had thus incurred the laws righteous judgment. According to the law of God, where transgression of the law is, death must take place (Rom. 6:23; Ezek. 18:4). It is not a matter of God loving us, overlooking our sins, and forgetting about the laws judgment. If God were to do this, His very throne would topple. God is bound by His own law to judge sin. What can He do?
Since God desired to save us and since we could not pay the debt of sin ourselves, He in His mercy decided to do so Himself. Two thousand years ago, Jesus Christ, the incarnate God, came to die on the cross to pay the debt for our sin. Having no sin Himself, He alone was qualified to die this substitutionary death. His death, being reckoned by God as ours, was acceptable to God, and He raised Him from the dead. Now when we believe in Christ, His death is counted in Gods sight as our own. Thus, our debt of sin is righteously paid, and we are saved.
Now, can God take back this salvation which Christ has purchased? Absolutely not! Since the debt was paid, for God to demand it again from us would be unrighteous. The same righteousness which formerly called for our condemnation now calls for our justification. What powerful security this gives to our salvation! Even a worldly judge would not demand the same fine to be paid twice. Certainly God, the source of all justice and righteousness, cannot do so. As Watchman Nee wrote in a hymn:
For me forgiveness He has gained,
And full acquittal was obtained,
All debts of sin are paid;
God would not have His claim on two,
First on His Son, my Surety true,
And then upon me laid.
Thus, the Bible declares that when God saves us, He shows forth His righteousness (Rom. 1:16-17; 3:25-26).
We Have Become Gods Children
When we were saved, we not only
received something; we also became something. We became children of God, born of His eternal life (John 1:12-13). A human father may be able to take back a gift he has given to his child, but he can never take back the human life which he has imparted. Although the child may misbehave, the child is still the fathers. In the same way, we are Gods children. Although we may have many weaknesses and may require His discipline, our sins and weaknesses cannot change the fact that we are His children. The life we received by our second birth is the eternal life, the indestructible life, the life of God, the life that can never die. Once we are born again, we can never be un-born.
God Is Strong
Another reason for the security of our salvation is Gods strength. God is unwilling to allow anything or anyone to snatch us from Him. Jesus said, I give to them eternal life, and they shall by no means perish forever, and no one shall snatch them out of My hand. My Father...is greater than all, and no one can snatch them out of My Fathers hand (John 10:28-29). The hand of the Father and the hand of the Lord Jesus are two strong hands holding us fast. Even if we try to run away from our Father, it would be impossible. Not only is God stronger than Satan, He is also stronger than we are.
God Never Changes
If it were possible to lose our salvation, many of us would have lost it long ago. As human beings, we go through many changes. One day we are hot; the next, cold. But our salvation is not based upon our erratic feelings. It is rooted and grounded in a God who is unchanging in His love and faithfulness toward us (Mal. 3:6). James 1:17 says, The Father of lights, with whom is no variation or shadow cast by turning. Lamentations 3:22-23 says, His compassions do not fail; they are new every morning. Great is Your faithfulness. If He loved us enough to save us, He surely loves us enough to keep us in that same salvation. Great is His faithfulness!
Christ Has Promised
Finally, Christ Himself has promised to keep us, uphold us, and never leave us. Although men often are unrighteous in keeping their promises, Christ will never fail to accomplish what He pledges. Listen to His promise: Him who comes to Me I shall by no means cast out (John 6:37); I shall by no means give you up, neither by any means shall I abandon you (Heb. 13:5). The Lords promises here are unconditional. By no means, that is, under no circumstances whatever, will He ever cast us out or cease to uphold us. This is His faithful promise.
What powerful security our salvation has! We have Gods selection, His predestination, His calling, His love, His grace, His righteousness, His life, His strength, His unchanging faithfulness, and His promises as the foundation, guaranty, and security of our salvation. We can all declare with Paul: I know whom I have believed, and I am persuaded that He is able to guard my deposit unto that day (2 Tim. 1:12).
THE JOY OF SALVATION
We have seen the assurance of our salvation, that is, how we know that we are saved. We have also seen the security of our salvation, that is, how we can never lose our salvation. But is that sufficient? Unfortunately, many Christians are content to go only this far
having salvation, but having little joy or
enjoyment of that salvation.
Our friend with millions in the bank may have the
assurance that he is rich, and he may have the
security of knowing that his deposit is safe. But if he never spends a dime and is content to live a paupers life, we can hardly say he has the
enjoyment of those riches. Objectively speaking he is rich, but in his practical experience he has nothing.
This is the condition of many Christians today. They are saved, but in their daily life they have little experience of the unsearchable riches of Christ (Eph. 3:8). However, Gods intention is that we not only have Christ, but that we enjoy Him, even to the uttermost (John 10:10; Phil. 4:4). The normal condition of a Christian is to exult with joy that is unspeakable and full of glory (1 Pet. 1:8).
But nearly all of us will admit that there are times, even many times, when we do not have this overflowing joy. Does this mean that we have lost our salvation? Absolutely not! Our salvation is based upon God, not upon us. But although we cannot lose our salvation, we can lose the joy of that salvation.
The Loss of Joy
What are the things, then, that cause us to sometimes lose our joy? The first item is sin. Joy depends on our having unbroken fellowship with God, but sin separates us from Him and causes Him to hide His face (Isa. 59:1-2).
The second item is grieving the Holy Spirit (Eph. 4:30). When we are saved, we become Gods temple and have His Spirit indwelling us (1 Cor. 6:17, 19; Rom. 8:9, 11, 16). This Spirit within is not a force or a thing, but a living person, Jesus Christ Himself (1 Cor. 15:45; 2 Cor. 3:17; 13:5). Like every living person, He has feelings and attitudes. Thus, when we speak or do things contrary to Him, He is grieved within us. When the Holy Spirit is grieved, our spirit, which is joined to Him (1 Cor. 6:17), is grieved, and we lose our joy.
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