Question: "What does the Bible say about bitterness?"
Answer: Bitterness is resentful cynicism that results in an intense antagonism or hostility towards others. The Bible teaches us to “get rid of all bitterness, rage and anger, brawling and slander, along with every form of malice.” It then goes on to tell us how to deal with such bitterness and its fruits by being “kind and compassionate to one another, forgiving each other, just as in Christ God forgave you” (Ephesians 4:31-32).
As an adjective, the word bitter means “sharp like an arrow or pungent to the taste, disagreeable; venomous.” The idea is that of the poisonous water given to the women who were suspected of committing adultery in Numbers 5:18: “the bitter water that brings a curse.” In its figurative sense bitterness refers to a mental or emotional state that corrodes or “eats away at.” Bitterness can affect one experiencing profound grief or anything which acts on the mind in the way poison acts on the body. Bitterness is that state of mind which willfully holds on to angry feelings, ready to take offense, able to break out in anger at any moment.
The foremost danger in succumbing to bitterness and allowing it to rule our hearts is that it is a spirit that refuses reconciliation. As a result, bitterness leads to wrath, which is the explosion on the outside of the feelings on the inside. Such unbridled wrath and anger often lead to “brawling” which is the brash self-absorption of an angry person who needs to make everyone hear his grievances. Another evil brought on by bitterness is slander. As used in Ephesians 4, it is not referring to blasphemy against God or merely slander against men, but to any speech springing from anger and designed to wound or injure others.
All this then leads to a spirit of malice, which signifies evil-mindedness or feelings of intense hatred. This kind of attitude is sensual and devilish in its influences. Malice is a deliberate attempt to harm another person. Therefore, “every form of malice” must be done away with (Ephesians 4:31).
The person who is bitter is often resentful, cynical, harsh, cold, relentless, and unpleasant to be around. Any expression of these characteristics is sin against God, and those who persist in them will not inherit His kingdom (Galatians 5:19-21). Hebrews 12:15 warns us to “see to it that no one misses the grace of God and that no bitter root grows up to cause trouble and defile many.” We must always be wary of allowing “bitter roots” to grow in our hearts; such roots will cause us to fall short of the grace of God. God wills that His people live in love, joy, peace, and holiness—not in bitterness. Therefore, the believer must always watch diligently, being on guard against the grave peril of bitterness.