Hebrews 12:15

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 ¹  and causing trouble, and through him many become defiled.

Hebrews 12:25

12:25 Take care not to refuse the one who is speaking! For if they did not escape when they refused the one who warned them on earth, how much less shall we, if we reject the one who warns from heaven?

[12:15]  ¹ tn Grk “that there not be any root of bitterness,” but referring figuratively to a person who causes trouble (as in Deut 29:17 [LXX] from which this is quoted).