For this is the will of God, your sanctification: that you abstain from sexual immorality; that each one of you know how to control his own body in holiness and honor, not in the passion of lust like the Gentiles who do not know God (1 Thess 4:3-5).
After Jesus tells his disciples that “unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven” (Matt 5:20), he gives six different areas where the law has been misunderstood by the Pharisees. So misunderstood, the law would forbid literal murder, but say nothing about bitterness and insult, ban adultery but remain silent on lust, and could be used in a way that could obscure sin—such as making oaths in such a way that makes it a bit more acceptable to be dishonest in their absence.
What I find interesting is that only murder and adultery, or anger and lust, are given as sins that will surely lead one to hell. Why that is, Jesus doesn’t say. Perhaps the commands forbidding both are foundational in a way that is unusually destructive to the covenant community, or perhaps they are particularly corrosive to the soul, so that the one engaging in either inevitably falls away from the Lord. In either case, these two are to be avoided with the greatest of effort and conviction.
They are also perhaps the two greatest temptations of men. Certainly they are among them. In my experience, anger and lust are two sins that men turn into virtues. I cannot count how many times I have heard lack of sexual control be extolled as a mark of manliness. Or the unwillingness to take an insult silently and humbly, without retaliation. In other words, we have glorified sins that we are too weak, or too unwilling, to mortify. There are of course times and ways to be angry—be angry, but do not sin (Ps 6)—and times and ways to take a woman as a wife. But these require a measure of vision and self-mastery that few are willing to exercise. Instead, we turn cowardice into virtue, confirming the truth of Paul’s words that “though they know God’s righteous decree that those who practice such things deserve to die, they not only do them but give approval to those who practice them” (Rom 1:32).
Keep constant watch over anger and lust, and do whatever you need to do, however severe, to flee both. And do not expect encouragement from the world. It will encourage you to embrace both.