Sayyiduna Jabir bin Abdullah (may Allah be pleased with both of them) narrates: The Jews used to say: A child becomes cross-eyed when a man has intercourse with his wife from behind. So Allah Almighty revealed this verse: "Your wives are your fields; so come to your fields as you wish." This means: come from the front or come from the back, but only come to the place where one is supposed to come.