I wasn't surprised by it — well, not too surprised by it — and made sure I didn't drown it: I turned on the water less strongly than normal, so as not to splash it. My hands clean, I opened the bathroom window, gave the spider my fuller attention, helped it get out of the sink, found where it then hid under the counter, got it onto a piece of toilet paper, and let it go out of the window.
Leaving the spider for another of the house residents to find would've been cruel and wrong.
I'm sure the spider was happier, and I certainly was. That was this morning.
Another highlight of the day involved no spiders at all (other than the many spiders who are always close to us, whether we're inside or outside): Mom drove into Portland to visit. We went to coffee (Rain or Shine Coffeehouse at SE 60th and Division), walked on Mt. Tabor — yes, a full-fledged extinct volcano in SE Portland, and that is cool — and the further indulgence of fast food and a cone at the nearby Dairy Queen, before Mom drove me back to where I live. We went on to other things today.
Did the spider go on to find flies to eat? I hope so!