Numbers 33:55 – But if ye will not drive out the inhabitants of the land from before you; then it shall come to pass, that those which ye let remain of them shall be pricks in your eyes, and thorns in your sides, and shall vex you in the land wherein ye dwell.
Ecclesiastes 3:1,8 – To every thing there is a season, and a time to every purpose under the heaven….A time to love, and a time to hate; a time of war, and a time of peace.
God is loving, longsuffering, and merciful even while He hates, takes vengeance, and executes justice.
Most of the time, the best course is to live and let live, to forgive and make peace. Every now and then, however, making nice just makes you a victim.