Heroin addiction is poignantly tragic. Users build tolerance, so larger hits are required for the same high. Soon the dosage they seek is more than enough to kill them. When addicts hear someone has died from an exceptionally strong batch, their first thought may not be fear but “Where can I get that?”

C. S. Lewis warned of this downward spiral in Screwtape Letters, his imaginative look at a demon’s explanation of the art of temptation. Start with some pleasure—if possible one of God’s good pleasures—and offer it in a way God has forbidden. Once the person bites, give less of it while enticing him to want more. Provide “an ever increasing craving for an ever diminishing pleasure,” until finally we “get the man’s soul and give him nothing in return.”

Proverbs 7 illustrates this devastating cycle with the temptation of sexual sin. Sex is God’s good gift, but when we seek its enjoyment outside of marriage we’re “like an ox going to the slaughter” (v. 22). People stronger than us have destroyed themselves by pursuing highs that are harmful, so “pay attention” and “do not let your heart turn to [wrongful] ways” (vv. 24–25). Sin can be alluring and addicting, but it always ends in death (v. 27). By avoiding—in God’s strength—the temptation to sin, we can find true joy and fulfillment in Him.