Three offenses they forgot and one they could not forgive (or vice versa) for Krishna-Shishupala? (That's one angsty adversarial relationship I absolutely love.)
1. He almost drops the message bringing word of the Emperor’s death, so deep is his grief; in so many ways, Jarasandha had been the father Shishupala had wanted for so long, who understood that there were more things than blood that made a family what it was. None but that damned Yadava could have puzzled out the secret of how to do it, he is sure--why, the Emperor hadn’t even confided in Shishupala himself!
But slowly, painfully, he forces himself to calm his breathing and see sense once more. It was all done in service of putting Cousin Yudhisthira on the throne, something that--while not more useful to Chedi’s interests--will at least not be less useful. Yudhisthira is a good man, and a good King, and can be counted upon to treat his mother’s nephew with kindness. It is only logical that he and his brothers should have wanted to usurp Jarasandha, or--that cowherd should have guided them in it.
He can forgive this. He can.
2. Mother says: “Don’t anger your cousin” so many times in a day that Shishupala wants to ask who her son is, him or that jumped-up upstart. Besides, who is Mother to question what he does with his judgment or time, whether he steals cows or maidens from his neighbors? He is King, now that Father’s dead, and that means he need answer to no one.
He watches her turn from him, with a frown of disapproval, and he does not even mind that sweet-voiced Vasudev has managed to lure yet another loved one away from him. Mothers are only needed until a boy is weaned; after that, they require a man’s influence to mature them. He does not mind at all.
At least she’s stopped nagging him like the nuisance she is.
3. Shishupala is a sensible man, after all, and once the initial shock has passed, he sends a conciliatory message to Dwaraka, as one should.
Women are silly, stubborn things (he writes) and he will not let the whims of one interfere in the loving relationship between cousins. Of course he forgives his uncle’s son the lack of experience not to know when a guileful princess is entrapping him; and naturally Shishupala will be happy to receive his cousin once more, provided he disposes of the girl once he tires of her.
He hasn’t any idea why his message is returned, torn in two and clearly stamped upon.
&1. He is curious about this cousin, as any would be; only newly returned from the wilds, more comfortable with cows, and with all the fascination in his fifteen-year-old heart, Shishupala images befriending him, teaching him all the ways of royalty. He has never had a friend before, growing up in Chedi, and he wishes very much that this might change soon.
But this Krishna only looks askance at all Shishupala’s favorite rituals, and complains of their comforts; and when Shishupala demands, exasperated, if all the luxury they enjoy does not please him, Krishna only looks at him with laughing eyes and says: “Why, yes; but that does not mean it cannot be better.”
That, oh, that is when Shishupala knows they will neither of them ever understand the other, and that he cannot forgive.