KJV: He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.
NASB: 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, to destroy the works of the devil.
KJV: If any man see his brother sin a sinwhich is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.
NASB: If anyone sees his brother committing a sin not leading to death, he shall ask and God will for him give life to those who commit sin not leading to death. There is a sin leading to death; I do not say that he should make request for this.