Sura al-Fatḥ 48:18

لَّقَدْ رَضِىَ ٱللَّـهُ عَنِ ٱلْمُؤْمِنِينَ إِذْ يُبَايِعُونَكَ تَحْتَ ٱلشَّجَرَةِ فَعَلِمَ مَا فِى قُلُوبِهِمْ فَأَنزَلَ ٱلسَّكِينَةَ عَلَيْهِمْ وَأَثَٰبَهُمْ فَتْحًا قَرِيبًا

llaqad raḍīa allāhu ʿani l-muʾminīna idh yubāyiʿūnaka taḥta l-shajarati fa-ʿalima mā fī qulūbihim fa-anzala l-sakīnata ʿalayhim wa-athābahum fatḥan qarīban

Allah's Good Pleasure was on the Believers when they swore Fealty to thee under the Tree: He knew what was in their hearts, and He sent down Tranquillity to them; and He rewarded them with a speedy Victory;