Um?? His purpose for Christians is more than that. Seeking His glory first is Biblical but the only thing you seek is not. Plus your joy? Yes that is a fruit of the Spirit & to have passion for His glory & your joy is part of it but what about all the other souls perishing? Getting Him the glory first but then there's also the sanctification process, fruits of the Spirit, dying to self &; sin, preaching the Word to others, helping others, prayer, caring for the brethren. If these things are the only things you think god's purpose was for you then it's no wonder you were blind as a bat to your own legalistic 5 point Calvinist self-centeredness. This extreme Calvinism blasphemes God's character & you use "sovereignty" & "getting God the Glory" words & phrases to lie to yourself.I hope for your sake you repented from this atrocity.
