A reason why no man should glory. If we are God's workmanship, our salvation cannot be of ourselves. His is emphatic. His workmanship are we.
Created (κτισθέντες)
See on Joh 1:3. The verb originally means to make habitable, to people. Hence to found. God is called κτίστης creator, 1Pe 4:19, and ὁ κτίσας he that created, Rom 1:25. Compare Rev 4:11. Κτίσις is used of the whole sum of created things, Mar 10:6; Rom 8:22.
Afore prepared (προητοίμασεν)
Rev, more correctly, prepared. Made ready beforehand. God prearranged a sphere of moral action for us to walk in. Not only are works the necessary outcome of faith, but the character and direction of the works are made ready by God.