Turn the other cheek. This obviously comes from Jesus. Whether you believe in him or not it’s still a powerful spiritual teaching I recommend to follow (although it’s a hard one).
If someone causes you an offence, the tendency is to strike back. I have committed this mistake many times in my life, and I still do. But it’s wrong. Jesus was right.
If instead of seeking vengeance you make yourself vulnerable to another offence from your offender, being mild as an innocent lamb waiting to be executed, without reflecting the hate, you might suffer another strike but it’s more likely that you will teach your offender a lesson by inspiring him/her humanity and compassion.
Why is it worth? First of all because your resentment is an unworthy illusion. By following it, nothing good will sprout for yourself and others. But if you manage to win that illusion you will feel free and empowered. Most importantly, you would break the chain of hate, thus bringing more love and understanding to this world.
Others are just your mirror, never forget this.