He promised to show mercy to our fathers
and to remember his holy covenant.
This was the oath he swore to our father Abraham,
to set us free from the hands of our enemies,
Free to worship him without fear,
holy and righteous in his sight
all the days of our life. (Canticle 16, BCP 92)

In the passage from Paul’s letter to the Galatians appointed for this morning, the apostle quotes the same passage we read today from the Book of Isaiah.

The prophet uses the image of a childless woman being blessed with children to symbolize Israel’s restoration to God’s favor. Paul extends the metaphor, widening the circle to include “children of the promise,” that is, the Gentiles (Gal. 4:23).

Like Isaac, who was born as a sign of God’s promise to Abraham, the Gentiles are also heirs of that promise. Paul’s extended argument is to remind the Galatians that their hope rests on God’s promise, not on observance of the law. Or, as he puts it elsewhere, “since all have sinned and fall short of the glory of God, they are now justified by his grace as a gift, through the redemption that is in Christ Jesus” (Romans 3:23-24).

In the Collect for Grace, usually read on Wednesday mornings, we not only thank God for bringing us “in safety to this new day” but also go on to ask that he “direct us to the fulfilling of [his] purpose; through Jesus Christ our Lord” (BCP 100).

We seek to be “holy and righteous in God’s sight” because of our gratitude at being children of the promise. We then go on to use the gifts God has given us as children of purpose, whose mission is to bring ever more people within the reach of Christ’s saving embrace.