"ALL have sinned and come short of the glory of God" Romans 3:23
"There is NONE righteous NO NOT ONE" Romans 3:10
If we can attain sinless perfection in this life then God lied to us. According to Hebrews 6:18 it is impossible for God to lie.
We can come close but this is rare and we need to fight the battle up here (hand raised high) and not down here (hand near the floor).
That is why God commanded us to be perfect even as your heavenly Father who is perfect. (Matthew 6:48)
You need to see the context between the verses in Matthew and the one in Ephesians. In Matthew, Jesus was speaking to the Jewish people and not the church. The Church and Israel being separate is an important distinction to make. Also, when that passage was spoken, the Jews were still under the law this is why Jesus made a condition to FORGIVE in order to be FORGIVEN. In the Ephesians passage Jesus had already died was buried and rose from the dead. The context here is the church in Ephesus which is where the Church today takes its doctrine from. You are commanded to FORGIVE since you have already been FORGIVEN due to Christ dying on the cross to pay for your sins. You are now under grace but do not use grace as a license to sin.
THe Luke passage applies to brotherly love and relationships between each other, not with God. This has nothing to do with salvation.
the 1 John 1:9 passage states that if we we confess our sins GOd cleanses us from ALL unrighteousness. This is when we, as lost sinners realise that we are sinners before a Holy God and turn to him and He cleanses us from ALL unrighteousness. FOr the saved person, this is when we sin and confess it and turn from it and God forgives us and fellowship with Him is restored. In both cases we are cleansed and have a clear conscience.
1. No he is not. If you believe that Jesus and baptism saves, then you are basing your salvation off of a works base. Ephesians 2:8-9,
THe person also robs God of is glory since he is playing a part in his salvation GOd clearly states in Isaiah 42:8 that He will not give His glory to anyone.
THe person also denies the sufficiency of the Sacrifice of Jesus on the cross.
2. Yes and No. The saved person can have this belief early in his Christian walk by influences from false teachers but if he is truly saved, the Lord will direct his paths in the ways of righteousness. As a child of God, GOd takes care of His own like a loving father. THe person who professes salvation but has this belief may not be truly saved and this can be God showing the person to examine himself to see if he is in the faith and needs to repent and turn to Christ alone for salvation.
3. Yes and No. No, because the Jesus of the Bible states clearly in John 14:6. Based on the statement above, the person is believing a false christ who is the way to Heaven for some but not for others. At the same time, let's say this person is truly saved. If he beleives this, his walk with the Lord is crippled as he will have a hard time witnessing to people and will be casting doubt to the lost. THat person needs to read his Bible and beleive it without question knowing that it is 100% truth.