Meister Eckhart

To be sure, this requires effort and love, a careful cultivation of the spiritual life, and a watchful, honest, active oversight of all one's mental attitude towards things and people.Its not to be learned by world-flight, running away from things, turning solitary and going apart from the world. Rather, one must learn an inner solitude, wherever or with whomsoever he may be. He must learn  to penetrate things and find God there, To get a strong impression of God firmly mixed on his mind.