When we connect Acts 26:18a with Luke 15:8, we see that the enlightening of the Holy Spirit is to open people’s eyes and to turn them from darkness to light and from the authority of Satan to God. The Spirit opens the believers’ eyes and turns them from darkness to light that they may see the divine things in the spiritual realm. To see these things requires spiritual sight and divine light.
To turn from darkness to light is to have a transfer from darkness into light, and to turn from the authority of Satan to God is to be transferred out of the authority of Satan into God. Darkness is a sign of sin and death; light is a sign of righteousness and life (John 1:4; 8:12). The authority of Satan is Satan’s kingdom (Matt. 12:26), which belongs to darkness. Satan is the ruler of this world (John 12:31) and the ruler of the power of the air (Eph. 2:2). He has his authority and his angels (Matt. 25:41), who are his subordinates as principalities, powers, and rulers of the darkness of this world (Eph. 6:12). Hence, Satan has his kingdom, the authority of darkness (Col. 1:13).
According to Acts 26:18a, we are transferred from the authority of Satan to God. Actually, to be transferred to God is to be transferred to the authority of God, which is God’s kingdom belonging to light. Formerly we were in darkness under the authority of Satan, but we have been transferred out of darkness and the authority of Satan into light and God.
Darkness is actually the authority of Satan. Whenever we are in darkness, we are under satanic authority. Light is God Himself (1 John 1:5). Therefore, when we are in the light, we are in God. Just as Satan and darkness are one, so God and light are one. The greatest transfer we can have is the transfer from darkness to light. When we are separated unto God by the Spirit, we experience such a transfer.
The Spirit enlightens the believers that they may repent. Hebrews 6:4a speaks of both repentance and enlightenment. Only through the Spirit’s work of enlightening us are we able to repent and turn to God.
The believers are those who have been convicted by the Spirit concerning sin, righteousness, and judgment. John 16:8-11 says, “Having come, He will convict the world concerning sin, and concerning righteousness, and concerning judgment: concerning sin, because they do not believe in Me; and concerning righteousness, because I go to the Father and you no longer behold Me; and concerning judgment, because the ruler of this world has been judged.” The Spirit always convicts people concerning the three matters of sin, righteousness, and judgment. Sin entered through Adam (Rom. 5:12), righteousness is the resurrected Christ (1 Cor. 1:30), and judgment is for Satan, who is the author and source of sin (John 8:44). We were born of sin in Adam. The only way to be freed from sin is to believe in Christ, the Son of God. Because we believe in Him, He is righteousness to us, and we have been justified in Him (Rom. 3:24; 4:25). Those who do not repent of the sin in Adam and believe in Christ will remain in sin and share the judgment of Satan for eternity (Matt. 25:41).
The convicting work of the Spirit is related to Adam, Christ, and Satan. Sin is related to Adam, righteousness is related to Christ, and judgment is related to Satan. We became fallen in Adam, but we have believed in Christ and have been justified. Because Christ was accepted by God in His death, God raised Him up from among the dead, and now He becomes righteousness to all who believe in Him. Satan, the source of death, has been judged and destroyed through Christ’s death (Heb. 2:14). Whereas those who believe in Christ receive Him as their righteousness, those who do not believe in Christ will suffer the judgment of Satan.
One day the Spirit came to us to separate us unto God by convicting us concerning sin, righteousness, and judgment. We repented, believed in the Lord Jesus, and escaped the judgment that is upon Satan. Through the convicting work of the Spirit we have been sanctified unto God.