The energy of grace is the power of spiritual fire that fills the heart with joy and gladness, stabilizes, warms and purifies the soul, temporarily stills our provocative thoughts, and for a time suspends the body’s impulsions. The signs and fruits that testify to its authenticity are tears, contrition, humility, self-control, silence, patience, self-effacement and similar qualities, all of which constitute undeniable evidence of its presence.
~St Gregory of Sinai (Philokalia, vol.4, p.262)