7 When my soul fainted within me I remembered the LORD: and my prayer came in unto thee, into thine holy temple.
[AD 420] Jerome on Jonah 2:7
"When my soul fainted within me I remembered the LORD." LXX: 'when my spirit failed in me, I remembered the Lord'. Although I hoped for no aid, he says, the memory of the Lord saved me, according to this passage: "I remembered the Lord and I rejoiced" [Ps. 76:4], and in another passage, "I remembered former days and I remembered the days of eternity" [Ps. 76:6]. I had lost all hope of finding a way out: my body was so frail in the intestines of the whale that I could not hope for my life. And so, everything that seemed impossible I found to be surpassed by the thought of the Lord. I saw myself imprisoned in the intestines of the whale, and all my hope was the Lord. From this we can learn that, according to the Septuagint, at the time when our spirit fails us, it is wrenched from its union with the body, and we ought not to turn our thoughts from Him who inside and outside our body is the Lord. For the Saviour the interpretation is not very difficult because he said, "my spirit is sad to die" [Mt. 26:38; Mk. 14:34], and "My Father, if it is possible let this cup pass me by" [Mt. 26:39], and, "I place my spirit in your hands" [Ps. 30:6; Lk. 23:46], and other passages which are similar to this. And my prayer came in unto you, into thine holy temple. LXX: similar. In my distress I remembered the Lord so and my prayer came in to heaven from the depths of the sea and from the roots of the mountains, and came to your holy temple where you reside in eternal beatitude. This new kind of speech should be noted here: a prayer made for a prayer. Jonah asks that his prayer rise up to the temple of God. He wishes like the Pope that in his body the people should be freed.

[AD 444] Cyril of Alexandria on Jonah 2:7
where the sea monster probably lurked in rocks and in sea caves. bars of the earth have enclosed me forever Now, the fact that he was not dead, as I said, but was alive in the sea monster, and suffered nothing in it contributing to death or corruption, would easily be grasped from his having hopes of his being rescued. Consequently he says, And you will raise up my life from corruption, he prays to emerge into the light, and be delivered up from the sea monster’s stomach as though from Hades.
[AD 865] Haimo of Auxerre on Jonah 2:7
Although he ought to have been corrupted and digested in the belly of the whale and diffused through the veins and joints of the fish, he came out safe and whole.
calling the God who is common to all his own and personal God; because of the magnitude of such great favor, he especially feels that God is his God ad Lord.
[AD 1022] Symeon the New Theologian on Jonah 2:7-8
When a person has completely abandoned the world, it seems to one that one is living in a remote desert, full of wild beasts. One is filled with unutterable fear and indescribable trembling, and cries to God like Jonah from the whale, from the sea of this life, or like Daniel18 from the pit of the lions and the fierce passions, or like the three children from the burning furnace and the flames of innate desire, or like Manasseh20 from the brazen statue of this earthly mortal body. The Lord hears that person and delivers him from the abyss of ignorance and love of this world, just like the prophet who came out of the whale, never to go back again.

[AD 1591] John of the Cross on Jonah 2:7
When this purgative contemplation oppresses a man, he feels very vividly indeed the shadow of death, the sighs of death, and the sorrows of Hell, all of which reflect the feeling of God’s absence, of being chastised and rejected by Him, and of being unworthy of Him, as well as the object of His anger. The soul experiences all this and even more, for now it seems that this affliction will last forever.