Sunan an Nasai
3128
Sahih+2

Abu Hurairah said:"A man came to the Messenger of Allah (ﷺ) and said: 'Tell me of an action that is equal to Jihad.' He said: 'I cannot. When the Mujahid goes out, can you enter the Masjid and stand in prayer and never rest, and fast and never break your fast?' He said: 'Who can do that?

SahihAbu Ghuddah
SahihAl-Albani