Then they need to preach Jesus, NOT the law.
Then spake Jesus again unto them, saying, I am the light of the world: he that followeth me shall not walk in darkness, but shall have the light of life. (Joh 8:12 KJV)
Because once someone has come to Jesus it is a sin to keep teaching salvation over and over again. Must go from milk to meat, you know. Can't stay a babe forever.
Hebrews 5:8 Though he were a Son, yet learned he obedience by the things which he suffered;
Hebrews 5:9 And being made perfect, he became the author of eternal salvation unto all them that obey him;
Hebrews 5:10 Called of God an high priest after the order of Melchisedec.
Hebrews 5:11 Of whom we have many things to say, and hard to be uttered, seeing ye are dull of hearing.
Hebrews 5:12 For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not of strong meat.
Hebrews 5:13 For every one that useth milk is unskilful in the word of righteousness: for he is a babe.
Hebrews 5:14 But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to discern both good and evil.
Hebrews 6:1 Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God,
Hebrews 6:2 Of the doctrine of baptisms, and of laying on of hands, and of resurrection of the dead, and of eternal judgment.
Hebrews 6:3 And this will we do, if God permit.
Hebrews 6:4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,
Hebrews 6:5 And have tasted the good word of God, and the powers of the world to come,
Hebrews 6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.
Hebrews 6:7 For the earth which drinketh in the rain that cometh oft upon it, and bringeth forth herbs meet for them by whom it is dressed, receiveth blessing from God:
Hebrews 6:8 But that which beareth thorns and briers is rejected, and is nigh unto cursing; whose end is to be burned.
Hebrews 6:9 But, beloved, we are persuaded better things of you, and things that accompany salvation, though we thus speak.
Hebrews 6:10 For God is not unrighteous to forget your work and labour of love, which ye have shewed toward his name, in that ye have ministered to the saints, and do minister.
Hebrews 6:11 And we desire that every one of you do shew the same diligence to the full assurance of hope unto the end: