Nahum 1:7 comes without any explanation or warning, which only serves to make the contrast with Nahum 1:3–6 even more obvious. The Lord whose wrath is poured out like fire (Nahum 1:6) is now described as good, a stronghold and refuge for those he knows. The goodness of the Lord almost always refers to his covenant faithfulness.1 This goodness is often experienced by his people when they are in trouble of any sort. He is their refuge, a place of safety for the people he knows. Those people he knows are the people with whom he has entered into a covenant relationship. They in turn take refuge in him. They respond to his covenant promises with ongoing faith. In this context, the Lord’s covenant faithfulness is expressed in his judgment of Nineveh. As he judges the cruelty of Judah’s enemy, the Lord is showing mercy and faithfulness to those he knows, namely the people of Judah. To know them is to care for them. By judging his people's enemy, he provides refuge and is a stronghold to them—those who are experiencing trouble from the Assyrians.2
The goodness of God is again seen supremely in the cross of Christ. At the cross, God’s wrath and salvation meet. His terrifying judgment and his goodness to those people he knows come together in one act. It is by coming to the cross that those who trust in him will find refuge from trouble.
7 The LORD is good, a stronghold in the day of trouble; he knows those who take refuge in him.