Peace of soul is acquired by a perfect surrender to the Divine Will, without which nothing happens…. He, in whose heart humility and meekness are reborn, will find rest for his soul. He will be satisfied with everything, grateful for everything, peaceful and full of love for everybody. He will judge none and will feel no anger. His heart will be filled with divine sweetness, that is, he will feel in himself the Kingdom of God because God grants His grace only to the humble.

Staretz Anthony of Optina
“Russian Mystics”