What does Isaiah 26:19 mean?
The ultimate expression of God's grace is His resurrection of those who come to faith in His Son, Jesus (1 John 3:1–3). Isaiah has been clear (Isaiah 26:16–18) that Israel has been unfaithful to the Lord. Isaiah's generation is one of many which squandered the opportunity to be used effectively by the Lord (Numbers 14:20–23). Had they remained fully faithful to Him, keeping the covenant the Lord made with them, He would have given them endless victory over their enemies (Deuteronomy 28:1–7). Their legacy would have been bringing justice and peace to the world.Instead, Israel was unfaithful to God. The nation repeatedly suffered the distress of God's punishment as they were defeated by those they could have overcome with the Lord's blessing on them. The nation fell behind and failed to deliver the earth from wickedness.
The Lord has remained faithful both to His purposes and to His people. He is faithful to His purpose in that He raised up the Messiah, His own Son, from the people of Israel. Through Jesus, the Lord has, and will accomplish, what He could have done through faithful Israel. God will ultimately bring judgment on the earth and blessing to all the nations through Christ.
God's promises to Israel are never failing in this: when the Messiah has won that ultimate victory, He will raise His people from death to new life in new physical bodies (1 Corinthians 15:51). Isaiah declares in this verse that the dead will live. Alive once more, the dead who belonged to the Lord will sing for joy. The earth will be refreshed by the awakened dead as the dew refreshes the ground in the morning. Isaiah completes his metaphor about childbirth by describing the birth that the Lord will finally bring about: the dead reborn to new life (Isaiah 26:17–18).
The Old Testament rarely describes resurrection. One of the few places is in Daniel 12:2: "And many of those who sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt." One reason the Old Testament doesn't often touch on resurrection may be because it can only be understood in the context of Christ. Jesus, the Messiah, had to be resurrected following His death on the cross to demonstrate God's final plan for human forgiveness. Paul leaves no room for doubt: resurrection is the destiny of every believer. There's no point to Christianity without it (1 Corinthians 15:12–28).