The ruling on a person saying to one who has done him a favor: “This is from the grace of Allah, and I thank you”?

Question:
May Allah reward you, O honorable Shaykh. Is it obligatory for a person to say to one who has done him a favor: “This is from the grace of Allah, and I thank you,” or is it sufficient to thank him while believing that all blessings are from Allah?

Answer:
You thank the created being according to what he has done for you. The Prophet (peace and blessings be upon him) said: “If someone does you a favor, then reward him. If you do not find with which to reward him, then pray for him until you see that you have rewarded him.”