Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah (PBUH) said, "Do not greet the Jews and the Christians before they greet you; and when you meet any one of them on the road, force him to go to the narrowest part of it."[Muslim].
This Hadith prohibits Muslims from greeting non-Muslims first. It also tells us that when the road is crowded, we should use the middle of the road and let the non-Muslims use its sides. This Hadith shows the dignity of Muslims and the disgrace and humiliation of the non-Muslims.