Narrated by Sahl b. Sa'd that the Prophet (ﷺ) said:

“Verily, in Paradise there is a gate called al-Rayyan. Those who used to observe the fast will enter through it on the Day o f Resurrection, none shall enter through it except them. It will be said, ‘Where are those who used to fast?’ They will get up, and none will enter through it except them .”

Bukhari (no. 1896) and Muslim [1152],