Sulaymān ibn Dawūd (Prophet Solomon) (peace be upon him) said: "I will indeed have sexual intercourse with seventy women at night, and each one of them will give birth to a child who will fight in the cause of Allah."
Authentic hadithعن أبي هُريرة رضي الله عنه عن النبيِّ صلى الله عليه وسلم قال: "قال سليمان بن داود -عليهما السلام-: لَأَطُوفنَّ الليلةَ على سَبْعينَ امرأةً، تَلِدُ كلُّ امرأةٍ منهن غُلامًا يقاتلُ في سبيلِ الله، فقِيل له: قل: إن شاءَ الله، فلم يَقُلْ، فطافَ بهنَّ، فلم تَلِدْ منهن إلا امرأةٌ واحدةٌ نصفَ إنسانٍ". قال: فقال رسولُ الله صلى الله عليه وسلم : "لو قالَ: إن شاء الله لم يَحْنَثْ، وكان دَرَكًا لحاجتهِ".
Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Sulaymān ibn Dawūd (peace be upon him) said: 'I will indeed have sexual intercourse with seventy women at night, and each one of them will give birth to a child who will fight in the cause of Allah.' It was said to him: 'Say: Allah willing!' But he did not do so. He had intercourse with them all, but none of them gave birth, except for one woman who gave birth to half a person." Upon this, the Messenger (may Allah's peace and blessings be upon him) said: "If he had said, 'Allah willing,' he would not have failed in his oath, and his desire would have been fulfilled."
Explanation
Prophet Sulaymān ibn Dawūd (peace be upon him) said to his interlocutor that he would have intercourse with seventy wives of his. It was permissible to combine such a number of wives in Sulaymān's time, or it was something specific to him. His intention was that each woman would give birth to a boy would who fight in the cause of Allah. His interlocutor told him to say: "Allah willing!" But he forgot to do so. He had intercourse with his wives, but none of them gave birth, except for one woman who gave birth to a stillborn. The Prophet (may Allah's peace and blessings be upon him) said that if Sulaymān had said "Allah willing", he would have fulfilled his oath and realized his wish.
Source · Narrated by Bukhari & Muslim
From the Hadith Encyclopedia (hadeethenc.com).