What is the ruling on one who says the closing salam before the imam while in a state of forgetfulness, then completes the prayer with the imam?

Question : The questioner from al-Qasim, whose name is indicated by the letter alif, alif, alif, says: A person said the closing salam before the imam out of forgetfulness, then realized it and completed the prayer with the imam and said the salam. What is required of him in this case?

Answer : Nothing is required of him, because if the one praying behind the imam makes a mistake in his prayer and nothing has been missed with the imam, then he does not have to perform the prostration for forgetfulness, because the imam bears the prostration for him.