Hebrews 12:14-15

Work at living in peace with everyone, and work at living a holy life, for those who are not holy will not see the Lord. Look after each other so that none of you fails to receive the grace of God. Watch out that no poisonous root of bitterness grows up to trouble you, corrupting many. (NLT)

Bitterness is defined as a feeling of antagonism, hostility, or resentfulness.

As a grim reminder of what can happen among believers, the writer warned that one who misses the grace of God may become like a bitter root whose infidelity to God affects others. 

Credits:

Christ in You -

Oracles Of A Worshipper by Keifer R. Bradshaw

God Favored Me - Hezekiah Walker

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