GENESI 38:9

Ma Onan, sapendo che quella progenie non sarebbe sua, quando entrava dalla moglie del suo fratelo, si corrompeva in terra, per non dar progenie al suo fratello.

And Onan knew that the seed should not be his; and it came to pass, when he went in unto his brother’s wife, that he spilled it on the ground, lest that he should give seed to his brother.