Al-Qasas 28:10

وَأَصْبَحَ فُؤَادُ أُمِّ مُوسَىٰ فَـٰرِغًا ۖ إِن كَادَتْ لَتُبْدِى بِهِۦ لَوْلَآ أَن رَّبَطْنَا عَلَىٰ قَلْبِهَا لِتَكُونَ مِنَ ٱلْمُؤْمِنِينَ

Wa-aṣbaḥa fuādu ummi mūsā fārighan in kādat latub'dī bihi lawlā an rabaṭnā ʿalā qalbihā litakūna mina l-mu'minīna

And the heart of Moses' mother became empty [of all else]. She was about to disclose [the matter concerning] him had We not bound fast her heart that she would be of the believers.