2.4. Recommendation to repeat greetings three times for large gatherings or doubt of being heard

One should repeat greetings three times when there are many peple in the gathering such that those who didn't hear the first will hear the second or third. One does the same if one thinks the other person did not hear and should not go beyond three times. This is based upon an-Nawawi's and Ibn Hajr's comments on the narration of Anas that the Prophet would repeat important statements three times.