OSAS doctrine helps Satan greatly by instilling a false sense of security and self-confidence among Christians concerning their salvation. They think they can't sin anymore and even if they do, no punishment will be due them as Christ paid for all our future sins.
I know of only one group that teaches once saved you can never sin again and that group is considered a cult.
1 John 3:4-12
4 Everyone who practices sin also practices lawlessness; and sin is lawlessness. 5 And you know that He appeared in order to take away sins; and in Him there is no sin. 6 No one who abides in Him sins; no one who sins has seen Him or knows Him. 7 Little children, let no one deceive you; the one who practices righteousness is righteous, just as He is righteous; 8 the one who practices sin is of the devil; for the devil has sinned from the beginning. The Son of God appeared for this purpose, that He might destroy the works of the devil. 9 No one who is born of God practices sin, because His seed abides in him; and he cannot sin, because he is born of God. 10 By this the children of God and the children of the devil are obvious: anyone who does not practice righteousness is not of God, nor the one who does not love his brother. 11 For this is the message which you have heard from the beginning, that we should love one another; 12 not as Cain, who was of the evil one, and slew his brother. And for what reason did he slay him? Because his deeds were evil, and his brother's were righteous. NAS
Did Paul live in constant fear of God revoking His gifts? I don't see that in Paul's teaching. You cannot
loose your salvation; you can however
choose the world over Christ when the circumstances of your life shifts your focus to you and off the Lord.