Is leaving off the greeting of the mosque a reprehensible act, and is it obligatory for one who sees a man leaving it off to command him to perform it, or not?

The questioner : He says: O esteemed Shaykh, is leaving off the greeting of the mosque a reprehensible act, and is it obligatory for me to command one who leaves off the greeting of the mosque to pray two rak'ahs?

The Shaykh : Leaving off the greeting of the mosque is a reprehensible act according to the opinion of some scholars who say that the greeting of the mosque is obligatory. This opinion is very strong and has a point of view, because So the Prophet (peace and blessings be upon him) interrupted his sermon to speak to this man, and he also commanded him to pray. If he is praying, he will be occupied with what? With listening to the sermon. It is well known that listening to the sermon is obligatory. Those who make the greeting of the mosque obligatory say: One does not occupy oneself with an obligatory act except with what? Except with an obligatory act. So if you see a person enter the mosque and sit down, say to him: Have you prayed? If he says: Yes, the matter is ended. If he says: I am not in a state of ritual purity, the matter is ended, because the command to pray does not apply to him while he is not in a state of wudu'. Good. If he says: I am in a state of wudu' and I have not prayed, you say to him: Get up and pray two rak'ahs, get up and pray two rak'ahs, so that you do not fall into sin, because those who hold that the prayer of the greeting of the mosque is obligatory believe that if a person leaves it off, he is sinful. Yes.