Here's a quote of the famous simile of the Turtle and the Fish by Bhikkhu Bodhi:
"There was once a turtle who lived in a lake with a group of fish. One day the turtle went for a walk on dry land. He was away from the lake for a few weeks. When he returned he met some of the fish. The fish asked him, "Mister turtle, hello! How are you? We have not seen you for a few weeks. Where have you been? The turtle said, "I was up on the land, I have been spending some time on dry land." The fish were a little puzzled and they said, "Up on dry land? What are you talking about? What is this dry land? Is it wet?" The turtle said "No, it is not," "Is it cool and refreshing?" "No it is not", "Does it have waves and ripples?" "No, it does not have waves and ripples." "Can you swim in it?" "No you can't" So the fish said, "it is not wet, it is not cool there are no waves, you cant swim in it. So this dry land of yours must be completely non-existent, just an imaginary thing, nothing real at all." The turtle said that "Well may be so" and he left the fish and went for another walk on dry land. "
Is this simile found anywhere in the Suttas? I thought I heard somewhere that it was.
The non-doing of any evil,
The performance of what's skillful,
The cleansing of one's own mind:
This is the Buddhas' teaching.