Excerpt from John Gill's Bible commentary on Romans 8:29:
"This regards the everlasting love of God to his own people, his delight in them, and approbation of them; in this sense he knew them, he foreknew them from everlasting, affectionately loved them, and took infinite delight and pleasure in them; and this is the foundation of their predestination and election, of their conformity to Christ, of their calling, justification, and glorification."
Hey Ken
We always assume that predestination must be from spiritual death to spiritual life, as in unbeliever to believer. It can easily also be used in the smaller context. God predestines lots of things. True OT believers were still in Adam and not yet alive in Christ. They had the Promises as a result of their faith, and died having not received them, thus the predestination. From the spiritual side of things, they were predestined from Adam with (OT) faith to Christ with (NT) faith, since they were already appointed to eternal life from their OT faith. All that the Father gives me I shall not lose one of them, except Judas. Keep in mind, the passage specifically says that they were predestined to be conformed to the image of Christ. That can be taken as meaning from unbeliever to believer, as it is traditionally understood, but also can be understood in the smaller context as from OT believer to Christ believer.
As was pointed out in the link, Romans 8:29 is clearly speaking of a specific people. I believe these people were Israel. There were promises made to both spiritual and physical Israel. But the spiritual Israel everyone is saved. Perhaps this would distinguish Romans 8:29 from Romans 11:2. We'll see.
Do you see what I mean? God could have foreknown them already because of their OT faith. They still were not conformed, or begun to be conformed to Christlikeness if they had not yet trusted in the Gospel message and became 'in Christ'. That's when they begin to be conformed to Christlikeness by the Spirit indwelling. The process of being perfected (Gal 3:2-3).
