Early in my adoption into God's family, when I first believed, the thought of predestination, adoption and election were those comforting ideas I needed to stay the path. While I cannot say that I fully comprehend the concept, there has never been a bit of fear associated with this idea. Totally the opposite - comfort. Along the way of understanding I came to see that there was also a responsibility on my part to 'glorify god' in all I say and do as my role in predestination. So before there was time, an eternity before, there was a plan for me to use my fruits to glorify God, then came my execution of the plan. The sad part is that I know family and friends who have heard the Word, yet still choose not to believe and as a result, right now, I may not see them in Heaven.
I believe that Paul, a Jew, brings up the topic to insure that the Gentiles understand that they are chosen as well and will have all the rewards God can give as they continue to Believe. This also shows God's love for us.
God is all the time! All the time God is Good!