I apparently didn't do much of biology, but when I was in high school, my biology teacher made me to understand that it's only natural for tapeworms to be present in the gastrointestinal tract of man, to aid digestion. But on no occasion was I ever taught that the presence of cankerworms are needful for the heart to operate at its best.
But then, many of us have cankerworms residing in our hearts unknowingly. Little wonder, the Apostle Paul in Ephesians 4:31-31 wrote:
Let all bitterness and wrath and anger and clamor and slander be put away from you, along with all malice. Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you.
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Many of us are fast losing our lives because of the cankerworm called grudges; it sucks pretty fine even when the carrier don't know it.
"I'm a Christian" you would say, and in fact, you pray all day long. Yet, you still have load of grudges in your heart against a brother or sister who has unknowingly offended you the previous day, week, month, or year.
I'm afraid to tell such a person that he or she is under the snare of a great cankerworm.
And whenever you stand praying, forgive, if you have anything against anyone, so that your Father also who is in heaven may forgive you your trespasses.” Mark 11:25
This tells us that a mind preoccupied with grudges can't really profit in the realm of the spirit, as far as God blessings and promises are concerned.
James 4:1 says: "What causes quarrels and what causes fights among you? Is it not this, that your passions are at war within you?"
Truly, as humans, we are going to experience conflicts or some kind of clash between us and our friends, and even family members. But we must not allow this reality to disconnect us from God very best for our lives all because of grudges.
To conclude this piece, let's read Colossians 3:12-14 with a careful attention...
Put on then, as God's chosen ones, holy and beloved, compassionate hearts, kindness, humility, meekness, and patience, bearing with one another and, if one has a complaint against another, forgiving each other; as the Lord has forgiven you, so you also must forgive. And above all these put on love, which binds everything together in perfect harmony.