Musnad Ahmad Hadith 9920

It is narrated from Abu Huraira (may Allah be pleased with him) that some people said, "O Messenger of Allah (ﷺ), tell us of a deed that is equal to jihad." The Noble Prophet (ﷺ) said, "You do not have the strength for it" (he said this two or three times). The people said, "Please tell us, perhaps we can do it." The Noble Prophet (ﷺ) said, "The example of one who strives in the path of Allah is like that of a person who fasts during the day, stands in prayer at night, and humbles himself before the verses of Allah, and does not fall short in his fasting or prayer in any way, until that mujahid returns to his family."