is sin that harms a relationship between two people. Neither person has to be Christian; the principles here come from the Bible, but also from common sense of those who have observed how humans think and work, both intellectually and emotionally.
the one-day rule
Ephesians 4:26 says to not let the sun go down on one's anger. I believe this wholeheartedly, having dealt with anger that stewed over many sunsets. Sun-set anger is tremendous ammunition for Satan, ammunition he has used to great effect, to assault my well-being.
Matthew 5:23-24if your brother has something against you
Then if you offer your gift on the altar, and remember there that your brother has something against you, leave your gift there before the altar, and go. First, be reconciled to your brother, and then coming, offer your gift.
Note that according to Romans 12:1, we are to live our lives as living sacrifices. So Matthew 5:23-24 applies at many moments of our lives, and especially when we're doing a 'good deed'.
Matthew 18:15-22if you have something against your brother
But if your brother may sin against you, go and reprove him between you and him alone. If he hears you, you have gained your brother. But if he does not hear, take one or two more with you, "so that on the mouth of two" or "three witnesses every word may stand" *. But if he fails to hear them, tell it to the assembly. And if he also fails to hear the assembly, let him be to you as the nations and the tax collector. Truly I say to you, Whatever you bind on the earth will be, having been bound in Heaven. And whatever you loose on the earth will be, having been loosed in Heaven. Again I say to you, If two of you agree on earth as to anything, whatever they shall ask, it shall be to them from My Father in Heaven. For where two or three are gathered together in My name, there I am in their midst. Then coming up to Him, Peter said, Lord, how often shall my brother sin against me, and I forgive him? Until seven times? Jesus said to him, I do not say to you, Until seven times, but, Until seventy times seven.
Ephesians 4:25-27do it immediately
Therefore, putting off the false, "speak truth each with his neighbor," * because we are members of one another. "Be angry but do not sin;" * do not let the sun go down on your wrath, nor give place to the Devil.
- sometimes I might not know I'm angry
- anger of one person can anger another, and cause [bad] positive reinforcement
- afraid to talk to someone
- convince myself that it's not a big deal
- busy with work
- it's less pain to not deal with the issue
- there might be a timetable for two of the above passages, but the Matthew 18 one isn't explicit
thoughts on the above ideas
They are all lame
and they all suck
. They are excuses to not obey God!
- the immediacy noted in Ephesians and Matthew 5 show how much God cares about us "keeping short accounts"
- taken together, the Matthew passages eliminate the "you first!" excuse
- if you don't resolve an issue between you and someone who ticked you off, thinking of them will often make you think of what they did to tick you off — this is bad
- unattended anger can morph inot other emotions if left undealt-with
- anger prompts, or at least should prompt, action
- you cannot honor, nor glorify God, by not having a right relationship with your brother
- Matthew 18 makes it explicit to [initially] keep things on the "down low"
- these passages indicate how to solve relational problems with minimal pain — stewing always magnifies things (if the mold on cheese is lessening, that probably means the cheese has been consumed)
While obedience to God might seem personally harmful at times, it always benefits the church as a whole. For the above, disobedience basically assumes that your brother/sister is not a Christian, or at least not up to obeying pretty basic scriptures. There is no way to positively spin disobedience of the above verses.