The importance of giving and returning the greeting, and not replacing it with "good morning," "good evening," "welcome," or other such phrases?

The Shaykh : As for the second type, which I should point out, and this is also a recommended practice that has unfortunately been abandoned, it is that giving the greeting upon meeting is, praise be to Allah, still preserved in many Islamic countries, although some have begun to neglect this greeting. One of them meets his brother and says "good morning" or "good evening" to him, without initiating with "peace be upon you." And in some countries, if you give the greeting, they do not return the greeting to you, but rather say to you "welcome" or "greetings." This is a sin beyond which there is no greater sin, because Allah, Mighty and Majestic, says in the well-known verse: It is not hidden from any Muslim that the Islamic legal greeting, as we mentioned at the beginning of the discussion we referred to earlier, is one of the names of Allah, which He established on earth, so spread it among yourselves. Therefore, whoever gives this greeting to his Muslim brother, and the brother initiates with "welcome, greetings, good morning, good evening," and does not return the greeting, neither with what is better nor with what is less, this is a disobedience. It is obligatory for those Muslims to be mindful of this.