Allah's Messenger (ﷺ) said, "Were I not afraid that it would be hard on my followers, I would order them to use the siwak (as obligatory, for cleaning the teeth).
Sahih al-Bukhari Book 94, Hadith 15
← Previous Hadith One night the Prophet (ﷺ) delayed the `Isha' prayer whereupon `Umar went to him and said, "The prayer, O Allah's Messenger (ﷺ)! The women and children had slept." The Prophet (ﷺ) came out with water dropping from his head, and said, "Were I not afraid that it would be hard for my followers (or for the people), I would order them to pray `Isha prayer at this time." (Various versions of this Hadith are given by the narrators with slight differences in expression but not in content).

Sahih al-Bukhari Book 94, Hadith 14 Next Hadith → The Prophet (ﷺ) fasted Al-Wisal on the last days of the month. Some people did the same, and when the news reached the Prophet (ﷺ) he said, "If the month had been prolonged for me, then I would have fasted Wisal for such a long time that the most exaggerating ones among you would have given up their exaggeration. I am not like you; my Lord always makes me eat and drink."

Sahih al-Bukhari Book 94, Hadith 16