Allah said,

﴿لاَ تَدْرِى لَعَلَّ اللَّهَ يُحْدِثُ بَعْدَ ذَلِكَ أَمْراً﴾

(You know not, it may be that Allah will afterward bring some new thing to pass.) meaning, `We commanded that the divorced wife remains in her husband's house during the `Iddah period, so that the husband might regret his action and Allah decides that the husband feels in his heart for the marriage to continue.' This way, returning to his wife will be easier for him. Az-Zuhri said that `Ubaydullah bin `Abdullah said that Fatimah bint Qays said about Allah's statement,

﴿لاَ تَدْرِى لَعَلَّ اللَّهَ يُحْدِثُ بَعْدَ ذَلِكَ أَمْراً﴾

(You know not, it may be that Allah will afterward bring some new thing to pass.) "Taking her back.'' Similar was said by Ash-Sha`bi, `Ata', Qatadah, Ad-Dahhak, Muqatil bin Hayyan and Ath-Thawri.