Nahum 1: The Lord Is Awesome

Nahum predicted the fall of Nineveh of Assyria a century after Jonas. Nineveh has been evil to the Judah. Prophet Nhaum says that the Lord reigns. We read:

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God is serious business.
    He won’t be trifled with.
He avenges his foes.
    He stands up against his enemies, fierce and raging.
But God doesn’t lose his temper.
    He’s powerful, but it’s a patient power.
Still, no one gets by with anything.
    Sooner or later, everyone pays.
Tornadoes and hurricanes
    are the wake of his passage,
Storm clouds are the dust
    he shakes off his feet.

Although the Lord doesn't lose his temper, He will punish Niniveh because He is righteous; sooner or later, everyone pays.
Sometimes we may think that God in Old Testament is different from the merciful Lord in the New Testament; however we read:

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God is good,
    a hiding place in tough times.
He recognizes and welcomes
    anyone looking for help,
No matter how desperate the trouble.

The Lord loves the one in trouble. He is merciful and helpful, specially to his chosen people.