God's Work
It stands under the apostolic promise that "he who began a good work in you will perfect it until the day of Christ Jesus" (Phil. 1:6). Sanctification, no less than justification, is God's work.
Richard Gaffin, Resurrection and Redemption: How Eschatology and The Gospel Relate, Modern Reformation (Philadelphia, PA: Alliance of Confessing Evangelicals, 1999), 25