What is the ruling on greeting loudly upon entering the mosque, and the disturbance this causes, as well as greeting with the hand immediately after prayer, and greeting a worshipper who is reciting remembrances, which leads to interrupting his remembrance?

Some jurists are of the opinion that greeting someone engaged in remembrance (dhikr) is not recommended, and that the person remembering is not obliged to return the greeting, while others say it is obligatory.

The Hanafis hold that one should not greet a reciter of the Quran or someone engaged in remembrance, and if they are greeted, returning the greeting is not obligatory, though some say it is.

The Shafi'is mentioned that the preponderant view regarding someone deeply engrossed in supplication (du'a) is that greeting them is disliked, because it disturbs them and causes them hardship, and the same applies to someone deeply engrossed in remembrance.