I am feeble and severely broken; I groan because of the turmoil of my heart. Lord, all my desire is before You; and my sighing is not hidden from You. (Psalm 38:8-9)
C.H. Spurgeon, in his Treasury of David, discusses this passage:
Deep, hoarse, inarticulate is the voice of sorrow. The heart learns groanings that cannot be uttered; the voice fails to tone and tune to human speech. When our prayers seem more animal than spiritual, they nonetheless prevail with the pitiful Father of Mercy. He hears the murmur of the heart and the roaring of the soul, and in due time He comes to relieve the afflicted.
Words fail. The heart throbs, but lips are silent. No one--not even our dearest friends--can decifer our groans. We run--with all of our undone-ness--to our Soul Reader. Our Father of Mercy.