Ye have heard that it was said by them of old time, Thou shalt not commit adultery:
But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart [Matt. 5:27–28].
"For many years I have publicly made the statement that nobody but the Lord Jesus has ever kept the Law. One Sunday morning I repeated it in my message, and afterward a big, burly, red–faced fellow came to me and said, “You always say that nobody keeps the Law. I want you to know that I keep the Law!” By the way, he belonged to a cult although he attended services at the church I pastored. Since he claimed to keep the Law, I said, “All right, let’s look at it,” and I showed him verse 22 regarding hatred being the same as murder. He said that he kept that, although I don’t believe that he did. So I gave him verse 28 and said,“It says here that if you so much as look upon a woman to lust after her, you have committed adultery. Now look me straight in the eye and tell me that you have never done that.” He was red–faced to begin with, but you should have seen him then—he was really red–faced. He grunted some sort of epithet, turned on his heels, and walked out. Of course, he walked out! And I say to you, if you are honest, you will not claim to be keeping the Law. Remember that there were ten commandments. Although Matthew mentions only these two that Christ dealt with, I am of the opinion that He lifted all ten of them to the nth degree.
Oh, my friend, the Sermon on the Mount shows me that I have sinned and that I need to come to Him for mercy and help. To say that you are living by the Sermon on the Mount while all the time you are breaking it is to declare that the Law is not important." McGee, J. V. (1991). Thru the Bible commentary: The Gospels (Matthew 1-13) (electronic ed., Vol. 34, pp. 80–81). Nashville: Thomas Nelson.
"Mt 5:29 pluck it out and cast it from you. Jesus was not advocating self-mutilation (for this would not in fact cure lust, which is actually a problem of the heart). He was using this graphic hyperbole to demonstrate the seriousness of sins of lust and evil desire. The point is that it would be “more profitable” (v. 30) to lose a member of one’s own body than to bear the eternal consequences of the guilt from such a sin. Sin must be dealt with drastically because of its deadly effects." MacArthur, J., Jr. (Ed.). (1997). The MacArthur Study Bible (electronic ed., p. 1401). Nashville, TN: Word Pub.
You will be given a body fit for heaven or fit for hell. Your choice. Hell is described as everlasting fire (Matt. 25:41), everlasting punishment (Mt 25:46), everlasting destruction (2 Thess. 1:9).