Blessed are the pure in heart:
for they shall see God.
–Matthew 5:8 (KJV)–

I am he that liveth, and was dead;
and, behold, I am alive for evermore, Amen;
and have the keys of hell and of death.
–Revelation 1:18 (KJV)–

—

Bernard McGinn, The Foundations of Mysticism (Crossroad, 1991), ch. 5.

Robert Gregg, trans. Athanasius: The Life of Antony (Paulist Press, 1979).

Colm Luibheid, trans. John Cassian: Conferences (Paulist Press, 1985).