There are just as many websites on this topic as there are sand on the beach. We will try to explain the truth!
The Old Testament taught the Laws.
Romans 2:12 For as many as have sinned without law shall also perish without law: and as many as have sinned in the law shall be judged by the law;
James 2:10 For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all.
Matthew 5:18 For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
Jesus takes it a step futher by teaching that the very thoughts we have condemn us
Matthew 5:28 But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
Remember Forgiveness is freely given
1 John 1:9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
No matter what preachers might tell you with the line,
"once saved always saved",
he doesn't offer you a free,
"sin all you want, free, get into heaven ticket"!
Matthew 7:21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
Hebrews 6:4-6 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,and have tasted the good word of God, and the powers of the world to come,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.
Matthew 19:26....With men this is impossible; but with God all things are possible.
Remember Again Forgiveness is freely given
1 John 1:9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.