It has always been your choice

Do you think there is a limit to one's patience? If that limit is reached, should any action be justified?

I think the answers are yes and no.

There is really a limit to one's patience but not every action could be justified.
Let give an example:

Two guys, Mr A and Mr B were arguing over a football match and it was all peaceful till one of the guys used an abusive word. Mr. B was angry but he still kept his cool. Mr. A thought that the quietness from Mr. B would be explained as him being scared. He went ahead to further the insult Mr. B and called Mr. B's mom a weakling.

Mr. B angrily punched Mr. A and a fight ensued. Mr. B found another opportunity and punched A again and he was knocked out. He didn't stop there he picked up a wood and it landed on A's head.

He would have decided how far he wanted his anger to lead him, but he let his anger decide that.

Mr. A was totally wrong but the response from Mr. B belittled whatsoever Mr. A did.

This is what I'm saying;

You may not have control over the actions of others but you have control over yours.
Choose where the light leads.