How to purify the mind? By starving it of the bad food it runs after, namely, objective pleasures. And feeding it on the wholesome food, namely, thought of God.

First and foremost, make your heart pure. It is only purity that attracts Divinity. If the iron filings are rusted, even the most powerful magnet will not attract them. The iron filings may blame the magnet, saying it has no power. But the magnet tells them, “You may think as you please, I am not bothered. Get rid of the rust and become pure. Only then will I attract you.” In the same manner, how do you expect God to attract your mind, which is rusted with evil thoughts? See good, listen to good things, speak good and pleasant words, and undertake sacred activities. If you act in this manner, without your asking itself God will certainly bestow His grace on you. Contemplation on God is the only means to keep the senses pure. All the spiritual practices are meant to exercise control over the senses.

Bagavan Sri Sri Sri Sathya Sai Baba