"just as He chose us in Him before the foundation of the world, that we should be holy and blameless before Him."
* Whether as a kid being picked to play on a baseball team, or the high schooler who gets the part in a production, or the adult who is asked to join the firm, we as people want to be wanted. And, for the most part, when we are selected for something it's based on something: skill, appearance, wealth, reputation, etc.
So when we read that God chose His own for Himself, by Himself (the word "chose" here implies it), the emphasis is on His sovereign prerogative. He is God.
Too, when we consider when this choosing took place ('before the foundation of the world'), any contribution by which we could have influenced His choice is eliminated. We were not on the scene to have a say.
Many feel uncomfortable, if not downright angry with such truth. Pride produces resistance to God's sovereign decisions. Distrust does, too.
Yet, for those who have learned to trust Him, who have found Him infinitely faithful, there is rest in His goodness. I love Psalm 9:10, "And those who know Your name will put their trust in You." We don't trust Him more, because we don't know Him very well. The better we know Him, the more faithful we find Him to be.