Sūrah No.108. Revealed in Makkah, 3 verses. It is the smallest Sūrah of the Quran.
When the son of the Prophet a died, the enemies taunted him and called him ‘abtar’. This was a name the Arabs at that time gave to someone who had no sons and was considered to have no progeny. The Sūrah was revealed to give good tidings to the Prophet a that he would have abundance and grace.
The Prophet a has said: Whoever recites Sūrat al-Kawthar in his obligatory prayers will get to drink from the river of Paradise on the Day of Judgement and will be from the companions of the Prophet under the tree of Tūbā.
Note: This blessed reward will be for those who understand the message of the Sūrah and follow the teachings of the Quran and the Ahlul Bayt (a).
The Sūrah declares that the Prophet a has been given abundance and grace and his enemies are the ones who whose progeny will be cut off.
1) Grace and abundance are from Allah.
2) Some blessings may not be apparent in a present moment, but Allah knows the future and eventual end of all things.
3) Do not despair at the taunting of enemies.
The entire Sūra.
1) Check https://en.wikishia.net/view/Sura_al-Kawthar
What are some understandings of the word Kawthar?
Every intended action that does not begin with Bismillāh is ‘abtar’ (cut off i.e. does not achieve the actual goal of every action which is closeness to Allah).
The Holy Prophet a, Wasā’il al-Shī‘ah, 4:1194