It is narrated from Hazrat Usama (may Allah be pleased with him) that on the night of Arafah, I was riding behind the Noble Prophet (peace and blessings be upon him). When the sun had set, the Noble Prophet (peace and blessings be upon him) departed from the plain of Arafat. Suddenly, the Noble Prophet (peace and blessings be upon him) heard the noise of people rushing behind him, so he said, "O people! Go gently, make calmness obligatory upon yourselves, for hastening the mounts is not a virtue." Then, whenever there was a crowd of people, the Noble Prophet (peace and blessings be upon him) would slow down his mount, and wherever the path was open, he would increase the pace, until he reached Muzdalifah, and there he offered both the Maghrib and Isha prayers together.
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 21760
Hadith Gradingحکم دارالسلام:حديث صحيح، خ: 1666، م: 1286، وهذا إسناد حسن