Mukhtasar Bukhari

Narrated Ibn Abbas (may Allah be pleased with them) that ( (Hasbunallahu wa ni‘mal wakeel) ) was said by Prophet Ibrahim (peace be upon him) when he was thrown into the fire, and the Messenger of Allah (peace and blessings be upon him) also said these words when people said to him: "The disbelievers of Quraysh have gathered a great army against you, so fear them." Upon hearing this news, the faith of the companions (may Allah be pleased with them) increased and they said the same: "Allah alone is sufficient for us, and He is the best disposer of affairs."