The Quran

وَما أَفاءَ اللَّهُ عَلىٰ رَسولِهِ مِنهُم فَما أَوجَفتُم عَلَيهِ مِن خَيلٍ وَلا رِكابٍ وَلٰكِنَّ اللَّهَ يُسَلِّطُ رُسُلَهُ عَلىٰ مَن يَشاءُ ۚ وَاللَّهُ عَلىٰ كُلِّ شَيءٍ قَديرٌ

Muhammad Asad

Yet [remember:] whatever [spoils taken] from the enemy¹ God has turned over to His Apostle, you did not have to spur horse or riding-camel for its sake:² but God gives His apostles mastery over whomever He wills - for God has the power to will anything.

Lit., "from them": i.e., from the Banu 'n-Nadir.
I.e., "you did not have to fight for it, since the enemy surrendered without giving battle". The term fay' (a noun derived from the verb fa'a, "he returned [something]" or "turned [it] over") is applied in the Qur'an and the Traditions exclusively to war-gains - whether consisting of lands, or tribute, or indemnities - which are obtained, as a condition of peace, from an enemy who has laid down arms before actual fighting has taken place (Taj al-'Arus).