Ma'bad bin Sirin says that once I asked Hazrat Abu Sa'id Khudri (may Allah be pleased with him) whether he had heard anything from the Prophet (peace and blessings be upon him) regarding 'azl (withdrawal). He replied, "Yes! We asked the Prophet (peace and blessings be upon him) about 'azl, so the Prophet (peace and blessings be upon him) said, 'What is that?' We explained that a man's wife is breastfeeding a child, and during that time he approaches her, but he does not like her to become pregnant again, so he discharges outside. Similarly, a man may have a slave woman and no other wealth besides her; he approaches her but does not like her to become pregnant, so he practices 'azl. The Prophet (peace and blessings be upon him) said, 'If you do not do so, it will not make any difference, because the coming of children is connected to destiny.'"