Isaiah 54-58

54 - the barren woman will have many children, for God is her husband. God's covenant of peace is as sure with Israel as His promise to Noah never to flood the earth again, because Israel's righteousness is from God.

55 -

God invites you to eat and drink of His free food, instead of costly and malnourishing sin. He will forgive. His Word will bring fruit and joy to the earth.
56 - God will save Gentiles and eunuchs, too, but Israel's leaders are careless and immoral.
57 - Israel has worked hard and long at her idolatry. God lives with the contrite He has struck Israel, but she does not repent.

58 - Israel asks why God doesn't honor her fast: it's because she greedily oppresses the poor while fasting. If they will honor God by keeping His Sabbath He will bless them