And give a little background-- who was it from, context/circumstances, why it meant so much to you, etc.
This is mine: Some friends were putting on a play at a small neighborhood theater. They had been in rehearsals for several weeks. On the day the play was to open, the guy who was supposed to run the lights canceled out. The producer/director came to me that morning and asked me to fill in, as I had run lights for him once before.
I had never been to even one rehearsal of this play and didn’t know a thing about it. I went to the empty theater early the same day, went up in the light box, and with the script in front of me, read through the play from beginning to end and ran each of the light cues *seven *times. By this time the actors and techie people had arrived and were getting set up.
About half an hour before curtain, the director came to me and gave me his watch and said at 7 pm (or whatever) bring the house lights down and that would be the cue for the actors to move to the stage from where they were mingling in the audience, and the play would begin (yeah, modern, no physical curtain). There was no stage manager to give me the cues; it was strictly from the script. Sweating profusely, I did my thing. It all went perfectly, without a hitch.
When it was over, I came down to give the director back his watch and he said, “You have no idea how much it meant to me to have someone up there I knew I could trust.”
This was over 30 years ago, and that comment left an indelible mark on my soul. I pride myself on being one of the Reliable People of the World. If I say I will show up and do something, I absolutely will, and if I’m not there, it’s because I’m dead. That would be the only reason. For him to say that to me affirmed what I still consider one of my best personal qualities, and I have never forgotten it.