An elderly doctor and a Presbyterian minister were seated next to each other on the plane. The plane was delayed at the start due to some technical problems.

Just after taking off, the pilot offered his apologies to the passengers and announced that a round of free drinks would be served.

When the charming air-hostess came round with the trolley, the doctor ordered a gin and tonic for himself.

The hostess then asked the minister whether he wanted anything. He replied, "Oh no thank you. I would rather commit adultery than drink alcohol".

The elderly doctor promptly handed back his gin and tonic to the air-hostess and said, "Madam, I did not know there was a choice."