'Unrelenting' in the Bible

It would still bring me comfort,and I would leap for joy in unrelenting painthat I have not denied the words of the Holy One.

Set me as a seal on your heart,as a seal on your arm.For love is as strong as death;ardent love is as unrelenting as Sheol.Love’s flames are fiery flames—the fiercest of all.

Which used to strike the peoples in anger with incessant blows,Which subdued and ruled the nations in wrath with unrelenting persecution.

In that day the Lord will punish Leviathan the fleeing serpentWith His fierce and great and mighty sword [rescuing Israel from her enemy],Even Leviathan the twisted serpent;And He will kill the dragon who lives in the sea.

"This is what the sovereign Lord says: 'The Philistines have exacted merciless revenge, showing intense scorn in their effort to destroy Judah with unrelenting hostility.

"'You have shown unrelenting hostility and poured the people of Israel onto the blades of a sword at the time of their calamity, at the time of their final punishment.