Once a year

@rondetto Said

A man getting along in years finds that he is unable to perform sexually.

He finally goes to his doctor who tries a few things, but nothing seems to work. Eventually, as a last hope, the doctor refers him to an African medicine man.

The medicine man says, "I can cure this."
With that said, he throws a white powder into a flame and there is a flash with billowing blue smoke.

Then he says, "This is powerful healing but you can only use it once a year.
All you have to do is say '123,' and it shall rise for as long as you wish!"

The man then asks, "What happens when it's over, and I don't want to continue?"
The medicine man replies: "When your partner can take no more sex and is completely raddled, all she has to say is '1234', and it will then go down.

But be warned: It will not rise again for another year."

The old gent rushes home, anxious to try out his new powers.
That night he showers, shaves, and smothers himself in aftershave.

He slides into bed, cuddles up to his wife, says "123" and suddenly he has the "risen" like never before, just as the medicine man promised.

His wife turns over and asks, "What did you say '123' for?"