[14] With his sword as expiation, for it might have been permissible in their law, especially if it had been for the sake of Allah such as missing prayer or the like; this is a more correct view. However, Ibn Jarīr favored the view that Solomon began to rub down their legs and necks with the hand, not by the sword.
[15] The Prophet (ﷺ) said that one night Solomon said that each one of his wives would conceive a boy who would fight for the sake of Allah. He forgot to say ‘Allah willing,’ so only one of them gave birth to a deformed, dead baby. So Solomon sought Allah’s forgiveness. [Al-Bukhāri]