{ Indeed Allah has bought, from the Believers, their lives and their wealth, so that Jannah may be theirs; they fight in the cause of Allah, and kill and are killed, a promise of truth on Him in the Torah, the Injil, and the Qur’an. And who is more faithful to His covenant than Allah? So rejoice over the deal that you have pledged to; this is the great victory } Al-tawba 111

He (may His remembrance be exalted) is saying: Indeed Allah has purchased from the Believers their lives and their wealth in exchange for Jannah, a promise of truth on Him. He is saying that He (may His praise be exalted) has promised them Jannah, a promise of truth on Him, that He will fulfill it for them, in His revealed books the Torah, Injil, and Qur’an, if they live up to what they have contracted with Allah, and fight His enemies in His cause and to uphold His religion, and kill and are killed.