The mother of the faithful, ‘Aisha, peace and blessings of Allah be upon her, said: The Messenger of Allah (peace be upon him) said:
He who innovates something in this matter of ours [Islam] that is not of it will have it rejected [by Allah].[Bukhari & Muslim]
In one version by Muslim it reads:
He who does an act which we have not commanded, will have it rejected [by Allah].
This is one of two hadiths that encompass the entirety of Islam according to scholars. The first is “Verily actions are by intention…” which addresses the internal aspect of practicing Islam. Everything we do should be with the intention of pleasing Allah (swt) and by purifying our intentions we accomplish a great deal in our religion.
Scholars say that the acceptance of actions of Ibadah (worship) is based on the above two conditions:
The intention – the action should be done with sincerity, for the sake of only Allah.
It should be done in accordance with the Sunnah of the Prophet (sas).