A reader asks:

I was asked a while back, where does the triple blessing before the reading of the Holy Gospel come from, its source? Not what we pray as we make the signs of the Cross, but its history or background.
I have asked several people who I thought would know, or even how to find the answer, but no one has been able to find anything.
That’s when I decided to ask you.
It would be great if you can help!

I haven’t the foggiest idea. Anybody?