Who hath saved us, and called us with an holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus before the world began, Who hath saved us - From sin; the spirit of bondage, and all tormenting fear. This is the design of the Gospel.
And called us with a holy calling - Invited us to holiness and comfort here; and to eternal glory hereafter.
Not according to our works - We have not deserved any part of the good we have received; and can never merit one moment of the exceeding great and eternal weight of glory which is promised. See the notes on the parallel passages.
Before the world began - Προ χρονων αιωνιων. Before the Mosaic dispensation took place, God purposed the salvation of the Gentiles by Christ Jesus; and the Mosaic dispensation was intended only as the introducer of the Gospel. The law was our schoolmaster unto Christ, Galatians 3:24. See the parallel places, and the notes there.