The Messenger of Allah (ﷺ) did not observe fast in any month of the year more than in the month of Sha'ban, and used to say: Do as many deeds as you are capable of doing, for Allah will not become weary (of giving you reward), but you would be tired (of doing good deeds) ; and he also said: The deed liked most by Allah is one to which the doer adheres constantly even if it is small.
Sahih Muslim Book 13, Hadith 229
← Previous Hadith I asked 'A'isha (Allah be pleased with her) about the fasting of the Messenger of Allah (ﷺ). She said: He used to observe fast (at times so continuously) that we said: He has fasted (never to break), and he did not observe fast till we said: He has given up perhaps never to fast, and I never saw him observing (voluntary fasts) more in any other month than that of Sha'ban. (lt appeared as if) he observed fast throughout the whole of Sha'ban except a few (days).

Sahih Muslim Book 13, Hadith 228 Next Hadith → The Messenger of Allah (ﷺ) did not fast throughout any month except during ramadan. And when he observed fast (he fasted so continuously) that one would say that he would not break (them) and when he Abandoned, he abandoned (so continuously) that one would say: By Allah, perhaps he would never fast.

Sahih Muslim Book 13, Hadith 230