Sahih Muslim
The Book of Prayers (Kitab Al-Salat)
Book Number: 004 / Hadith Number: 1882
Abdullah b. Umar and Abu Huraira said that they heard Allah's Messenger (way peace be upon him) say on the planks of his pulpit: People most cease to neglect the Friday prayer or Allah will seal their hearts and then they will be among the negligent.