Are using antimony kohl, growing hair, eating Tharid, etc. habits practiced ordinarily by the Prophet (peace be upon him) or acts of worship to be rewarded when done?
Some scholars deemed such things mere habits. Others said that it is the manner that should be imitated — that is, what is significant here is the way the Prophet used antimony or ate Tharid. In Maraqi As-Su`ud (Stairs of Happiness), it is stated,
His innate deeds such as eating
And drinking are not acts of worship
The acts done by the Prophet as a human being are not actually legislated by Shari`ah, but it remains desirable to imitate his way of doing them. For example, if you want to use antimony kohl, you had better follow his example by starting with the right eye etc.
Yet, scholars differed on whether certain Prophetic deeds are considered as acts of worship or mere habits, such as performing Hajj while on the back of an animal (See hadith No. 1218 reported by Muslim from Jabir Ibn `Abdullah) or lying down for a while in between the supererogatory two-Rak`ah Prayer and the Fajr Prayer (See hadith No. 626 and 736 reported by Al-Bukhari and Muslim respectively from `A’ishah).
It is controversial whether such deeds are habits or acts of worship. Imam Ahmad deemed them desirable, while Imam Malik held that they were just habits. It was said in Maraqi As-Su`ud,
It is like performing Hajj while riding
And lying down after the Fajr Prayer
The matter is not problematic, In Shaa Allah. Whoever practices such deeds it will be good for him, and whoever does not do them there is no blame on him.