Quran 48:18 from Surah Al-Fath on Divine Marvels.
۞لَّقَدۡ رَضِيَ ٱللَّهُ عَنِ ٱلۡمُؤۡمِنِينَ إِذۡ يُبَايِعُونَكَ تَحۡتَ ٱلشَّجَرَةِ فَعَلِمَ مَا فِي قُلُوبِهِمۡ فَأَنزَلَ ٱلسَّكِينَةَ عَلَيۡهِمۡ وَأَثَٰبَهُمۡ فَتۡحٗا قَرِيبٗا
English translation: Certainly Allah was pleased Allah was pleased with the believers when they pledged allegiance to you under the tree and He knew what (was) in their hearts so He sent down the tranquility upon them and rewarded them (with) a victory near
Transliteration: laqad radiya al-lahu ani al-mu'minina idh yubayi'unaka tahta al-shajarati fa'alima ma fi qulubihim fa-anzala al-sakinata alayhim wa-athabahum fathan qariban