Romans 9:16 So then it is not of him that willeth, nor of him that runneth, but of God that sheweth mercy.
Let me remind you again that Paul is addressing Jews in Rome. We who are on the outside looking in will not have the same perspective as those in the Jewish community. In many ways our trying to understand this brings about some serious error as to one of Paul’s primary messages. Predestination is foreknowledge. God knew all that would happen in all of history before He began the work of creation.
Ephesians 1:4 According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love:
This is such an enormous issue that rendering a proper understanding is impossible from a viewpoint fixed in time. What amazes me more than the concept is the fact that God, knowing all the evil released into the world, all the hate, all the torture, murder, lusts, and evil mankind performs on mankind, He chose to set it all in motion anyway. This is how precious our love is to our God. He put up with all this to obtain just a remnant that would love Him.
Romans 8:18 For I reckon that the sufferings of this present time are not worthy to be compared with the glory which shall be revealed in us.
I see much suffering in this world which is unbearably ugly. Then I must accept that God sees His Glory, Jesus Christ in us, to be so great that all the ugliness is nothing. I cannot in my humanity imagine something that wonderful. Yet God saw it before He created anything of this world.
Your take away here should be this; you were worth it.