Is the prayer behind a masbuq considered a congregational prayer?

Q: I arrived for the 'Asr prayer and joined in the third rak'ah. After the imam finished the prayer, I stood up to complete the part of the prayer I had missed. During that time, a Muslim arrived and prayed behind me, making me his imam. Is it permissible for me to be his imam? And will his prayer be counted as a congregational prayer? Please inform us; may Allah reward you.

A: There is no harm in that, if Allah wills. According to the correct view, he is the ma'mum and you are the imam, and it is hoped that you will both receive the reward of the congregation. If he prays alone and you complete your prayer alone, there is no harm. However, if he prays with you, he should be on your right, not behind you, if he is the only one, as the Sunnah from the Prophet (peace and blessings be upon him) is authentic in this regard. And success is from Allah.