Hebrews 12:15-17
12:15 See to it that no one comes short of the grace of God, that no one be like a bitter root springing up and causing trouble, and through him many become defiled.
12:16 And see to it that no one becomes an immoral or godless person like Esau, who sold his own birthright for a single meal.
12:17 For you know that later when he wanted to inherit the blessing, he was rejected, for he found no opportunity for repentance, although he sought the blessing with tears.