Book of Habakkuk

The Book of Habakkuk is the eighth book of the 12 minor prophets of the Hebrew Bible. It is thought to be written by the prophet Habakkuk, in the late 7th century BC. In the first part of the book Habakkuk is talking with God about why people are allowed to do evil things. God tells him that He is going to allow the army from Babylon to come and defeat the people of Israel. This is to punish them for their sins of turning from God and treating people badly. Habakkuk then asks God why he would use the evil nation of Babylon to punish His own people. God replies that the people of Babylon will also later be punished. In the end Habakkuk accepts God's actions as good and responds with faith. 
Several verses in the book are well known. Chapter 2, verse 4 says "the just shall live by faith". This verse was used by Saint Paul in two of his letters and also by the writer of the letter to the Hebrews in the New Testament to show that we are accepted by God when we have faith in Him and this leads to right living. At the end of Chapter 3, Habakkuk states that even if all his crops and animals die and he is left poor, he will be glad in God who saves him. This is similar to what Job said when bad things happened to him.