"I suspect that religion is a necessary evil in the childhood of our particular species. And that's one of the interesting things about contact with other intelligences: we could see what role, if any, religion plays in their development."
- Arthur C. Clarke

The origin of this word seems straightforward enough, but if you look, you can find it earlier. Bear with me.

John FM Dovaston wrote a long poem Fitz-Gwarine: A Ballad of the Welsh Border in Three Cantos in 1811. It contains these lines:

Lord, when I look upon thy starry sky
With pearls empath'd like scatter'd dust of gold,
I humble me, lost in amazement high,
To think what he thy gifted son hath told,
Far-sighted Newton; that round each are roll'd
Un-number'd worlds.

Science fiction fans feel right at home in these lines. In The Empath episode of Star Trek: TOS, when Scotty learns about Gem, the young woman empath, he says "Scott comments that she must have been a "pearl of great price" and they all agree. Yes, the "pearl of great price" is a parable from the book of Matthew, but is there some sort of in-joke here that I don't know about?

The Star Trek TOS episode The Empath (1968) was striking enough that I remember it from childhood. In Star Trek: TNG, one of the main characters is an empath, counselor Deanna Troi.