Romans 3:1
What special privilege, then, has a Jew? Or what benefit is to be derived from circumcision?
Romans 2:25-29
Circumcision does indeed profit, if you obey the Law; but if you are a Law-breaker, the fact that you have been circumcised counts for nothing.
1 Corinthians 15:32
If from merely human motives I have fought with wild beasts in Ephesus, what profit is it to me? If the dead do not rise, let us eat and drink, for tomorrow we are to die.
Hebrews 13:9
Do not be drawn aside by all sorts of strange teaching; for it is well to have the heart made stedfast through God's grace, and not by special kinds of food, from which those who scrupulously attend to them have derived no benefit.