It is narrated from an Ansari companion that once we went out with the Prophet, peace and blessings be upon him, for the funeral of an Ansari. At that time, I was young and with my father. The Prophet, peace and blessings be upon him, sat by the edge of the grave and began instructing the one digging the grave: "Make it spacious at the head side, and make it spacious at the foot side. For him, there are many clusters in Paradise."
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 23465