John Calvin Commentary Isaiah 63:8

"For he said, Surely, they are my people, children that will not deal falsely: so he was their Saviour." — Isaiah 63:8 (ASV)

For He said, Surely they are My people. He mentions the election of the people and represents God as speaking of it, so that we may keep in view the purpose of our calling: that He wished to have a special people who would call upon Him.

And yet, he accuses the people of ingratitude for having disappointed God in His expectation. This is not because the Lord can be deceived, for He clearly foresaw what they would become and also declared it through Moses (Deuteronomy 32:15). Rather, Scripture speaks in this way when it is entirely due to the ingratitude of men that they disappoint God, as we previously saw.

I looked that it should yield grapes, and it has yielded wild grapes (Isaiah 5:4).

Nor does he discuss God’s secret decree, but speaks in human terms about the mutual agreement between God and believers, so that all to whom He graciously offers Himself as their Father may answer God when He calls; for the foundation stands sure, that none of the elect will perish, because the Lord knows who are truly His (2 Timothy 2:19).

Children that do not lie. We know that the purpose of our calling is that we may lead a holy and blameless life, as the whole of Scripture testifies, and as we have often stated in previous passages (Isaiah 43:21; Isaiah 55:5).

Justly, therefore, does the Lord say that He elected the people so that they might be holy and true, so that He might have children who were averse to falsehood and vanity.

But the people did not keep their promise and were far removed from that simplicity which they ought to have followed, for everything was full of deceit and hypocrisy. Nevertheless, He holds out the hope of pardon, provided that they flee to God and humble themselves through sincere repentance.

Therefore He became their Savior. The Prophet shows what is the primary part of the service of God: namely, to have a pure and upright heart. Hence it follows that God forsakes us because we are treacherous and are covenant-breakers. Since, therefore, this people took pleasure in their vices, it was proper first to convict them of their unbelief, so that, being afterwards converted to God, they might find Him to be their Savior.