For bitterness to set in a Christian needs to stop recognizing his or her position in grace before God. This allows Satan to plant a seed of bitterness that will poison the mind with resentfulness and result in a sharp, bitter, and unpleasant demeanor and lead a person to act out of doubt, which is sin.
Therefore as many as are mature, we should frame the mind this way, and if anyone of you frames the mind differently, also this the God will reveal to you. Philippians 3:15
What was from a beginning, what we have heard, what we have discerned with our eyes, what we have watched, and our hands touched concerning the Word of the life. And the life was manifested, and we discerned, and testify, and announce to you, the eternal life that was before the Father and was manifested to us.
