What is most important to us, dear brothers, is to ensure the propagation of the essence of Tawhid; the Tawhid of divinity in the souls of people, so that the goal of man is the face of Allah and the ultimate dwelling in all his affairs. His worship, behavior, relationships with others and all his affairs, because it is what is most important. That man’s intention, hope, repent followed by good actions and return, be devoted to Allah alone. And it is through this Tawhid, i.e. the divinity and worship, that the servant attains happiness in this life and the hereafter.

Source: Majmou’ Al Rassa-il Fadilat (7/ 351), Sheikh Mohammed Ibn ‘Otheimine, may Allah have mercy on him.