Sahih Muslim Book - 27, Hadith - 4286

وَحَدَّثَنَا مُحَمَّدُ بْنُ عَبَّادٍ وَابْنُ أَبِى عُمَرَ - وَاللَّفْظُ لاِبْنِ أَبِى عُمَرَ - قَالاَ حَدَّثَنَا سُفْيَانُ عَنْ هِشَامِ بْنِ حُجَيْرٍ عَنْ طَاوُسٍ عَنْ أَبِى هُرَيْرَةَ عَنِ النَّبِىِّ -صلى الله عليه وسلم- قَالَ « قَالَ سُلَيْمَانُ بْنُ دَاوُدَ نَبِىُّ اللَّهِ لأَطُوفَنَّ اللَّيْلَةَ عَلَى سَبْعِينَ امْرَأَةً كُلُّهُنَّ تَأْتِى بِغُلاَمٍ يُقَاتِلُ فِى سَبِيلِ اللَّهِ. فَقَالَ لَهُ صَاحِبُهُ أَوِ الْمَلَكُ قُلْ إِنْ شَاءَ اللَّهُ. فَلَمْ يَقُلْ وَنَسِىَ. فَلَمْ تَأْتِ وَاحِدَةٌ مِنْ نِسَائِهِ إِلاَّ وَاحِدَةٌ جَاءَتْ بِشِقِّ غُلاَمٍ ». فَقَالَ رَسُولُ اللَّهِ -صلى الله عليه وسلم- « وَلَوْ قَالَ إِنْ شَاءَ اللَّهُ. لَمْ يَحْنَثْ وَكَانَ دَرَكًا لَهُ فِى حَاجَتِهِ ».

It was narrated from Abu Hurairah that the Prophet (s.a.w) said: "Sulaiman bin Dawud, the Prophet of Allah, said: 'Tonight I will go around to seventy women, each of whom will give birth to a boy who will fight in the cause of Allah.' His companion, or the Angel, said: 'Say: "If Allah wills."' But he did not say it, or he was caused to forget, and none of his women gave birth to a child except one, who gave birth to a deformed child." The Messenger of Allah (s.a.w) said: "If he had said: 'If Allah wills,' he would not have broken his oath, and that would have been a means of attaining what he hoped for."