Isaiah 54:5 (ESV) … “For your Maker is your husband, the Lord of hosts is his name; and the Holy One of Israel is your Redeemer, the God of the whole earth he is called.”
The image in this chapter is that of Jehovah, the faithful husband, forgiving Israel, the unfaithful wife, and restoring her to the place of blessing. Isaiah has used the marriage image before (50:1–3) and will use it again (62:4). Jeremiah also used it (Jer. 3:8), and it is an important theme in both Hosea (chap. 2) and Ezekiel (chaps. 16 and 23). The nation was “married” to Jehovah at Mt. Sinai, but she committed adultery by turning to other gods; and the Lord had to abandon her temporarily. However, the prophets promise that Israel will be restored when Messiah comes and establishes His kingdom.
What kind of a restoration will it be? For one thing, it is a restoration to joy and therefore an occasion for singing (Isa. 54:1a). Isaiah is certainly the prophet of song; he mentions songs and singing more than thirty times in his book. The immediate occasion for this joy is the nation’s deliverance from Captivity, but the ultimate fulfillment is when the Redeemer comes to Zion and the nation is born anew (59:20).
It will also be a restoration to fruitfulness when the nation will increase and need more space (54:1b–3). The nation had been diminished because of the Babylonian invasion, but God would help them multiply again. At the end of this age, only a believing remnant will enter into the kingdom; but the Lord will enlarge the nation abundantly. Israel may feel like a barren woman, unable to have children; but she will increase to the glory of God. God will do for her what He did for Sarah and Abraham (49:18–21; 51:1–3). The tents will need to be enlarged, and the desolate cities will be inhabited again!
Paul quoted Isaiah 54:1 in Galatians 4:27 and applied the spiritual principle to the church: Even as God blessed Sarah and the Jewish remnant with children, so He would bless the church, though she is only a small company in the world. Paul was not equating Israel with the church or suggesting that the Old Testament promises to the Jews are now fulfilled in the church. If we claim the Old Testament Jewish prophecies for the church, then we must claim all of them, the judgments as well as the blessings; and most people do not want to do that!
Israel’s restoration to her land will also mean confidence (Isa. 54:4–10). Isaiah gives another one of his “fear not” promises (41:10, 13, 14; 43:1, 5; 44:2, 8; 51:7; 54:14) and explains why there was no need for the nation to be afraid. To begin with, their sins were forgiven (v. 4). Why should they fear the future when God had wiped out the sins of the past? (43:25; 44:22) Yes, the people had sinned greatly against their God; but He forgave them, and this meant a new beginning (40:1–5). They could forget the shame of their sins as a young nation, as recorded in Judges and 1 Samuel, as well as the reproach of their “widowhood” in the Babylonian Captivity.
Another reason for confidence is the steadfast love of the Lord (54:5–6). Jehovah is their Maker and would not destroy the people He created for His glory. He is their Redeemer and cannot sell them into the hands of the enemy. He is their Husband and will not break His covenant promises. As an unfaithful wife, Israel had forsaken her Husband; but He had not permanently abandoned her. He only gave her opportunity to see what it was like to live in a land where people worshiped false gods. God would call her back and woo her to Himself (Hosea 2:14–23), and she would no longer be “a wife deserted” (Isa. 54:6, NIV). She felt forsaken (49:14), but God did not give her up. 
It is important to know that God never gives up on us. God my chose to give us over to a particular sin in which we are unrepented of, but he does not give up on us calling us back. He will always have a heart that is a wooing heart which calls us back to his great love.