What is the ruling of Islamic law on a man boycotting some people because they did not offer him condolences on the death of his wife's father?

It is forbidden for a Muslim to boycott their Muslim brothers for not offering condolences, because boycotting without a valid Islamic reason is prohibited. The Prophet, peace and blessings be upon him, forbade it, and he forbade cutting ties, turning away from each other, and mutual hatred, and everything that could cause division between a Muslim and their Muslim brother. As for offering condolences to the family of the deceased, it is commendable.