Habakkuk had long been grieved by the apostasy and injustice in Judah. A sensitive man who trusted God completely, he could not understand why God allowed such rampant sin to go unpunished. Knowing God must have a reason for His actions, he asked in faith the question, "Why?" (1:3).
In love God honors Habakkuk's sincere question, but the answer caused him even greater concern: "For, lo, I raise up the Chaldeans, that bitter and hasty nation, which shall march through the breadth of the land, to possess the dwellingplaces that are not their's" (v. 6). God intended to use the vicious Babylonians to punish His chosen people (vv. 5-11).
This prompted the prophet's second question, "How?" How could God use such an evil people to punish the Jews (1:12-2:1)? God patiently explained that Israel's sins merited captivity, and furthermore that Babylon's sins would eventually be punished also.
Once Habakkuk knew God's plan, he did not dispute it. Rather, his concern turned to his people--soon to be in captivity. He was afraid they would lose all knowledge of God in a heathen culture, and he prayed, "O LORD, revive thy work" (3:2; literally "keep alive thy work"). This concern was answered by a majestic appearance of the pre-incarnate Christ (vv. 3-15), through which Habakkuk understood that God would indeed judge His enemies (v. 12) and deliver His people (v. 13).
Habakkuk's final response? Total submission to God's sovereign control over all things. He claims that in spite of these overwhelming problems (3:18), "yet I will rejoice in the LORD, I will joy in the God of my salvation." JDM http://www.icr.org/article/5742/