Those who pay regard to vain idols forsake their hope of steadfast love. (Jon 2:8 ESV)Jonah wasn't given an easy assignment; God told the Israeli prophet to enter then world superpower Assyria's capital of Nineveh and predict doom if the pagans didn't repent. Jonah fled from God's command and traveled by boat toward Tarshish (the opposite direction) until God caused a storm to occur and, long story short, Jonah was tossed overboard and swallowed by a large fish.
From the belly of the large fish Jonah, himself, repented—that is to say, he had a change of heart. This is where the powerful Scripture above arrives. Those who hold a love for idolatry in their hearts, "forsake their hope of steadfast love." The Hebrew word for "steadfast love" is chêsêd which can be translated in Scripture as mercy, goodness, kindness, faithfulness or lovingkindness. I prefer the phrase "covenant love" to express the power behind chêsêd. It is the faithful love that God shows the people of his covenant. In the Old Testament this meant the physical nation of Israel, the Mosaic Law People. In the New Testament this means the spiritual Israel, the Church, the New Covenant People of God.
God relents and has the fish vomit Jonah onto dry land. He preaches against Ninevah and the people repent from the king on down! God, in mercy, doesn't destroy them. Jonah becames angry and says to God
And he prayed to the LORD and said, "O LORD, is not this what I said when I was yet in my country? That is why I made haste to flee to Tarshish; for I knew that you are a gracious God and merciful, slow to anger and abounding in steadfast love, and relenting from disaster. Therefore now, O LORD, please take my life from me, for it is better for me to die than to live." (Jonah 4:2-3 ESV)Here was a preacher mad that his "congregation" heeded his sermon! Jonah didn't flee from God's assignment initially just because he was afraid but because he was afraid the Assyrians—Israel's enemy who would destroy Israel several years later—would repent and God wouldn't destroy them...and he was right!
Oh how fickle and depraved is the heart of man! What a contrast to the covenant love of God!