St. Seraphim of Sarov: God is a fire that warms and kindles the heart and inward parts...

God is a fire that warms and kindles the heart and inward parts. 

Hence, if we feel in our hearts the cold which comes from the devil - for the devil is cold - let us call on the Lord. 

He will come to warm our hearts with perfect love, not only for Him but also for our neighbor, and the cold of him who hates the good will flee before the heat of His countenance.

St. Seraphim of Sarov