Is the hadith, "Whoever stands with the Imam until he departs, it is recorded for him as if he stood the entire night in prayer," specific to the 'Isha prayer or Tarawih, and does it suffice for Qiyam al-Layl? And how can one achieve the reward of standing the entire night in prayer if one prays Tarawih in a mosque where the Imam prays eight rak'ahs and then leaves, and another Imam comes to complete the remaining rak'ahs and Witr? What is the ruling on friends separating from the Imam after eight rak'ahs and not completing the prayer with him?

The aforementioned hadith is authentic, and it is better for a man to pray with the Imam and perform Witr with him, for the Prophet, peace and blessings be upon him, said: "Indeed, if a man prays with the Imam until he departs, it will be recorded for him as if he prayed the whole night."

What some friends do, by not performing Witr with the Imam, causes them to miss out on this virtue. If they wish to pray after the Imam's prayer, they should make the Imam's Witr odd by adding one rak'ah, then pray as much as they wish, and perform Witr at the end of their prayer. This way, they combine two virtues: praying with the Imam until he departs, and making the last prayer of the night Witr.

Staying with the Imam until he departs does not contradict the hadith, because the Prophet, peace and blessings be upon him, did not say: "Whoever prays with the Imam and departs with him, it will be recorded for him as if he prayed the whole night." Rather, he made the culmination of the prayer "until the Imam departs." And whoever adds to his Imam after his salam has indeed prayed with him until he departed.

If the mosque has more than one Imam, it is better for the worshiper to remain until the second Imam departs, in order to attain the reward promised in the hadith.