Is it permissible for the one praying behind the Imam, who intends to delay Witr, to stand up after the Imam's tasleem from Witr (prayer) three times, in order to perform an additional rak'ah to make his prayer even, knowing that the night prayer is two by two (rak'ahs)?

Scholars have differed on what a follower (ma'mum) should do if he intended to pray two rak'ahs of night prayer (qiyam al-layl), but the Imam prayed Witr as three continuous rak'ahs. This issue is clarified in three sayings attributed to Malik: prohibition of adding a rak'ah, permissibility with dislike (karahah), and permissibility without dislike.

The reason for this difference stems from the fact that any action the follower takes will inevitably involve a problem. For example, if he gives the salutation (tasleem) after two rak'ahs, he would be separating from the Imam. Or, if he gives the salutation with the Imam, he would have prayed three voluntary rak'ahs, which is disliked by many scholars. Or, if he adds a rak'ah after the Imam's salutation, it would contradict the Prophet's (peace be upon him) saying: "The night prayer is two by two."

The correct position in this matter is to join the Imam and give the salutation with him. He has two options: 1. To give the salutation with the Imam. In this case, praying three voluntary rak'ahs is overlooked, because the necessity here is to follow the Imam. 2. To add a rak'ah, thereby praying four. In this case, praying four continuous voluntary rak'ahs is overlooked, and performing night prayer with four rak'ahs is permissible according to most scholars.

The last option is better, because if he gives the salutation with the Imam or adds a rak'ah, he would have prayed more than two rak'ahs in both cases. So, for him to end it with an even number (shaf') is better than ending it with an odd number (witr).