The Holy Spirit depicted in the form of a dove, as part of the "Preparation of the Throne" of Christ (source)
Heavenly King, Paraclete, [Comforter] Spirit of Truth, present everywhere, filling all things, Treasury of blessings and Giver of life; come and dwell in us, and cleanse us of every stain, and save our souls, O Good One.
Through the prayers of our Holy Fathers, Lord Jesus Christ our God, have mercy on us and save us! Amen!