"Can a saved person ever become unsaved?"
26
For if we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins,
27 But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.
28 He that despised Moses' law died without mercy under two or three witnesses:
29 Of how much sorer punishment, suppose ye, shall he be thought worthy, who hath trodden under foot the Son of God, and hath counted the blood of the covenant,
wherewith he was sanctified, an unholy thing, and hath done despite unto the Spirit of grace?
30 For we know him that hath said, Vengeance belongeth unto me, I will recompense, saith the Lord. And again,
The Lord shall judge his people.
31 It is a fearful thing to fall into the hands of the living God.
Hebrews 10:26-31
2Peter 1:5 And beside this, giving all diligence,
add to your faith virtue ... knowledge ... temperance ... patience ... godliness ... 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.
2Peter 1:8-9
20 For if after they have escaped the pollutions of the world through the knowledge of the Lord and Saviour Jesus Christ,
they are again entangled therein,
and overcome,
the latter end is worse with them than the beginning.
21 For it had been better for them not to have known the way of righteousness, than, after they have known it, to turn from the holy commandment delivered unto them.
22 But it is happened unto them according to the true proverb, The dog is turned to his own vomit again; and the sow that was washed to her wallowing in the mire.
2Peter 2:20-22
10 So those servants went out into the highways, and gathered together all as many as they found, both bad and good:
and the wedding was furnished with guests.
11 And when the king came in to see the guests,
he saw there a man which had not on a wedding garment:
12 And he saith unto him, Friend, how camest thou in hither not having a wedding garment? And he was speechless.
13 Then said the king to the servants, Bind him hand and foot, and take him away,
and cast him into outer darkness; there shall be weeping and gnashing of teeth.
Matthew 22:10-13