When the mind is stable and pure,the faculty of discrimination is sharpened, following which knowledge ripens and culminates in Bhakthi.
Bhakthi is a selfless, overpowering love for the Lord. This can be attained only when knowledge of the higher power is attained. This knowledge can be attained when you perform your action sincerely and efficiently.
Doing your duty to the utmost perfection of which you are capable is the foothold of all spiritual discipline.
One must work incessantly and, in the process, give up all mental attachment. It is possible to perform your duties in this manner only when you have a basic understanding of who you are, why you have come here, and what is to be attained. Knowledge and action are very closely linked. A man acts according to his knowledge. With knowledge as a base, when you perform your duties in the right manner, your mind becomes purified and the knowledge of the Self, or God, can then be preserved in the mind. When this knowledge ripens, love of God blossoms.