One day I received a phone call from someone who was kind in their approach to let me know that I had angered them. As we spoke and I listened, it became clear that what I had said hit a nerve because of things that I had no prior knowledge of.

Most of us are probably carrying something that is a trigger for us from a specific past experience.

We free ourselves when we recognize our triggers and release them (may require help to do so).
When we are offended, we have the opportunity to presume positive intent on the part of the other person, reflect on our responsibility to the trigger (address and resolve it) and/or humbly and courageously approach the other person to discuss.
When we are approached by someone who was offended by us, listen and ask questions. It is an opportunity to learn about the other person and ourselves.
None of us is responsible for another person’s historic triggers. We can still listen and engage with empathy.