I believed, therefore have I spoken - This, in the Septuagint and Latin Vulgate, begins a new psalm, but without any good reason. This language is borrowed by the Apostle Paul to express his confidence in the truth of the gospel, and the effect which that confidence had on him in causing him to declare the truth. 2 Corinthians 4:13. The meaning here is, that in the time of his affliction the psalmist had true faith in God; and, as a result of that, he was able now to speak as he did. At that time he trusted in God; he called on him; he sought his mercy, and God heard his prayer; and now, as the consequence of that, he was enabled to give utterance to these thoughts. Faith was at the foundation of his recovery, and he was now reaping the fruits of faith.
I was greatly afflicted - In danger of death. The psalmist reviewed this now, and he saw that all that he had felt and dreaded was real. He was in imminent; danger. There was occasion for the tears which he shed. There was reason for the earnestness of his cry to God.