This will probably offend you, but the church that would seem to agree with you is the Roman Catholic Church, which is known for dividing sin into venial and mortal and believing that the former can be "paid for" in Purgatory.
Well, I am not offended. First, I believe you are not seeing the Bible for what it plainly says. Second, you simply do not understand what I believe according to the Scriptures is all, as well. For I do not agree with the Catholic Church in any way in regards to Soteriology or in the way they worship God. Catholics believe sacred tradition to be on par with the Word of God and it is a part of their Soteriology. I do not agree with their added extra traditions that are not mentioned in Scripture (Which goes against Sola Scriptura of which they deny). For it is dangerous for a Catholic to place 100% trust in Jesus Christ alone and with having 0% trust in Mary and the Sacraments. I also do not believe there is a purgatory. But the Catholic church did not get the teaching of mortal versus venial sins from their own imaginations or traditions, though. That is something that comes directly from Scripture itself that the Protestant Church (that believes in OSAS) denies. For just because the Catholic Church believes in the Trinity does not mean that the Trinity is not true. Truth is determined by the Word of God. Anyways, 1 John 5:16-18 says there are sins that do not lead unto death and there are sins that do lead unto death. If you were to take a note pad and write down every time John had talked about life and death or light and darkness in his epistle, you would see that he was talking about contrasting spiritual life with spiritual death. For John was not concerned with a believer's physical life versus his physical death as a part of God's plan of salvation. In fact, it is an honor in God's Word for a believer to suffer and die for their faith. So staying alive physically is not our ultimate focus in our walk with God. Although, our body is the temple for our Lord, the primary focus of God and His Word is about our spiritual status with God.
What is an example of a sin that does not lead unto spiritual death?
Well, 1 John 3:4 says, "sin is transgression of the Law."
Laws are Commandments.
We are commanded in Scripture to be baptized.
But Peter says in 1 Peter 3:21 that baptism is not for the putting away of the filth of the flesh (i.e. sin) (Also see 2 Corinthians 7:1 in regards to the related words "filth of the flesh" being in reference to sin).
In other words, if a believer disobeys the command to be baptized, and they die, they will not be condemned for abiding in such a sin because it is a command that does not have any after-death consequences. Such a sin in this person's case is not a sin that leads unto death (i.e. spiritual death and not physical death).
But at the end of Romans 1, Paul lists certain sins for individuals whereby if they commit them, they are worthy of death. John says the same thing in Revelation 21:8. He mentions a certain list of sins and essentially says that those who do those types of sins will face the "second death" (Which is also known as the Lake of Fire). These sins can cause spiritual death for a person (if not confessed or forsaken - See 1 John 1:9, 1 John 1:7, 1 John 2:3-4, and Proverbs 28:13); Such sins are murder, theft, fornication, drunkenness, hate, lying, and idolatry, etc. These are sins that lead unto spiritual death (and not physical death) (See Romans 1, Ephesians 5, Galatians 5, 1 Corinthians 6, Colossians 3, and Revelation 21).
Even Jesus said himself there is a.... "GREATER SIN." Jesus also mentions how there is an unforgivable sin (Which is speaking bad words (i.e. blasphemy) against the Holy Ghost). So not all sin is the same (As you would desire for it to be).
Anyway, I get that you do sin, but not ones that would cost you your salvation, and that you believe that a state of sinlessness can be achieved in this life. Like it or not, this is not a very common view among Christians
Scripture says, narrow is the way that leads unto life, and FEW be there that find it. The popular belief in churches today is OSAS (Which is a sin and still be saved doctrine on some level). The popular belief in churches today is in denying that with God not all things are possible because they do not believe God can help a believer to stop sinning in this life.
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