The Kauthar (a river of Prophet Muhammad in Paradise)
100) Anas narrated: Prophet Muhammad one day took a nap among us and woke up laughing. We asked him: 0 Messenger of Allah, why did you smile. The Prophet said: A Surah was revealed to me before. Then he read out :"In the Name of Allah, the Most Beneficent, the Most Merciful": "Verily, We have granted you (0 Muhammad) AlKauthar (a river in Paradise). Therefore, tum in prayer to your Lord and sacrifice (to Him only). For, he who makes you angry(0 Muhammad) will be cut off" (SweatAl-Kauthar) Then the Prophet asked: Do you know what AlKauthar is? The narrator said we said: Allah and His Messenger know best. Then the Prophet said: It is a river in Paradise Allah pledged to give me. It is full of every thing good and my Ummah will aim at it on the Day of Resurrection. Its cups are as many as stars. Some of my followers will be prevented from it and I will ask 0 my Lord they are my followers. Allah will say: You (0Muhammad) do not know how they took to heterodoxy after you).
(This Hadith is sound and reported by Muslim, Abu Da'ud and Nas'ai).
This Hadlth reflects the danger of deviation from the Sunnah of the Prophet. Every good deed has two conditions to be accepted by Allah: One is that it should be done solely for Allah without any partner whatsoever. Second condition is that it should be performed according to the Sunnah, i.e. tradition of the Prophet