After making His economy, God started to carry out His economy in eternity past. The first step in God's carrying out of His economy was His selection. He foreknew us (1 Pet. 1:2a) and chose us in Christ before the foundation of the world (Eph. 1:4). Out of many millions of human beings, God chose you and me. He chose us by predestinating us (v. 5). To predestinate is to mark out beforehand. In eternity God saw us and chose us, so He marked us out. His choosing and marking out are actually one thing. We can illustrate this by considering the sisters' shopping at the supermarket. They may see many peaches there, but eventually they select some, mark them out, and purchase them. God chose us and marked us out in such a way in eternity.
Eventually, in time, God created man. After God's creation of Adam, Satan quickly acted to poison him. Later, in the New Testament time, God became a man. Then God as the Spirit continued to carry out His economy. He chose us and marked us out, but we became lost, so He came to seek us. This is fully unveiled in the Lord's parables in Luke 15. These parables show us how God the Father loves the son, how God the Son, for the sake of God the Father's love, came to redeem us, to gain us, to purchase us, and how the Third of the Trinity, God the Spirit, comes as a woman to do a seeking work, a finding work. She enlightened us from within and found us.
John 16 reveals that this finding Spirit convicted us concerning sin in Adam. He also convicted us concerning righteousness, causing us to realize that Christ is God's righteousness, that He wants to be our righteousness, and that we can be justified only in Him as our righteousness. Then this seeking Spirit convicted us of judgment (vv. 8-11). The universe is not without government. It is a universe in God's government, and there is a judgment. A person has the freedom to sin, but he has to realize that some day the Lord will judge him. Actually, the judgment in the lake of fire is reserved for Satan. If we do not repent of the sin that is in Adam and believe into Christ, the Son of God, as our righteousness, we will remain in sin and share the judgment of Satan for eternity (Matt. 25:41). When the Spirit convicted us concerning sin, righteousness, and judgment, we fully realized our position and our need. Then we repented and desired to turn to God and receive Christ.
This is the first aspect of the divine sanctification as revealed in 1 Peter 1:2. This aspect of the sanctification of the Spirit is before the obedience and the sprinkling of the blood of Christ. This aspect of sanctification before our repentance and believing is to find God's lost people, to bring them back, so that they can be made holy and become God's sons.
This is fully shown in Ephesians 1:4-5. In verse 4 we are told that God chose us to be holy. Then verse 5 says that in His choosing He predestinated us, marked us out, unto sonship. The word unto can be translated "for." God predestinated us for sonship. Thus, sanctification is a preparing step to make us sons of God. It is very much related to God's economy and to God's sonship. Sanctification does not stand alone. It is involved with God's economy from eternity and then with God's sonship in time.