{ Oh you who have believed! Shall I attest to you all of a transaction that will deliver you from painful punishment? That you believe in Allah and His Messenger, and wage jihad in the cause of Allah with your wealth and with yourselves; this is better for you, if only you knew. He will forgive your sins and will admit you into gardens below which rivers flow and pleasant dwelling places in gardens of Eden; this is the great victory. And other things that you love – support from Allah and impending victory. So give the good news to the Believers! } Al-saff 10-13

The word of the Most High: { Shall I attest to you all of a transaction } ; the expositors say that this verse came down when the people said: If only we knew what deeds are most pleasing to Allah, we would do them always. And so Allah attested to them concerning this, and gave it the status of a transaction due to the gain present in it.