Unrepentant brothers and sisters? They would not be brothers and sisters. Because they have not yet believed in the only name of Jesus, why do you think the people in john 6 left? Because they did not believe, Why do you think the people in james were called impostors? because they did not believe.
Did jesus lie? he did not say he who has not stopped sin is condemned already, he said he who does not believe.
Is unbelief unrighteousness? It is in the eyes of God.
If you are not in or on something can you fall from it. If I am already on the floor can I fall from the floor? But if I am on a stool I can fall from the stool. If I am in the Grace of God, I can also fall from the Grace of God. If I am already in condemnation can I fall into it. NO, I can't fall into something I am already in.
Hebrews 4:11 (KJV)
11 Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief.
2 Peter 3:17-18 (KJV)
17 Ye therefore, beloved, seeing ye know
these things before, beware lest ye also, being led away with the error of the wicked, fall from your own stedfastness.
18 But grow in grace, and
in the knowledge of our Lord and Saviour Jesus Christ. To him
be glory both now and for ever. Amen.
James 5:12 (KJV)
12 But above all things, my brethren, swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yea be yea; and
your nay, nay; lest ye fall into condemnation.
2 Peter 1:5-10 (KJV)
5 And beside this, giving all diligence, add to your faith virtue; and to virtue knowledge;
6 And to knowledge temperance; and to temperance patience; and to patience godliness;
7 And to godliness brotherly kindness; and to brotherly kindness charity.
8 For if these things be in you, and abound, they make
you that ye shall neither
be barren nor unfruitful in the knowledge of our Lord Jesus Christ.
9 But he that lacketh these things is blind, and cannot see afar off, and hath forgotten that he was purged from his old sins.
10 Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fall:
2 Peter1:10 ....if ye do these things, ye shall never fall:
Must mean we are somewhere we can fall from if we don't do these things. So if we are purged from sin and enter into the election of Christ through faith but do not keep these things God tells us to keep we can fall from the election we entered into as we turn from the faith given us.