5 And this Hannah in the first book of Kings, who was a type of the Church, maintains and observes, in that she prayed to God not with clamorous petition, but silently and modestly, within the very recesses of her heart. She spoke with hidden prayer, but with manifest faith. She spoke not with her voice, but with her heart, because she knew that thus God hears; and she effectually obtained what she sought, because she asked it with belief. Divine Scripture asserts this, when it says, “She spoke in her heart, and her lips moved, and her voice was not heard; and God did hear her.” We read also in the Psalms, “Speak in your hearts, and in your beds, and be pierced.” The Holy Spirit, moreover, suggests these same things by Jeremiah, and teaches, saying, “But in the heart ought God to be adored by you.”
Source: The Treatises of Cyprian (New Advent)