“But you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. Now if anyone does not have the Spirit of Christ, he is not His. And if Christ is in you, the body is dead because of sin, but the Spirit is life because of righteousness. But if the Spirit of Him who raised Jesus from the dead dwells in you, He who raised Christ from the dead will also give life to your mortal bodies through His Spirit who dwells in you.”
Whether someone is a true Christian or not is distinguished according to whether the Spirit of God dwells within him/her. How can someone be a Christian, whether he/she believes in Jesus or not, if he/she does not have the Holy Spirit within his/her heart? Paul tells us that whether we believe in Jesus is not the most important question, but whether we believe in Him having discovered the righteousness of God or not. The true faith required by the saints is the faith that is ready for the Spirit to dwell in them. The presence of the Holy Spirit in you will determine whether you are a Christian or not.
Thus, Paul said, “Now if anyone does not have the Spirit of Christ, he is not His.” He said “anyone.” It does not matter whether the person is a minister, evangelist, or revivalist. If one does not have the Holy Spirit within his/her heart, the person is not His. You must keep in mind that if you do not believe in God’s righteousness that leads you to receive the Holy Spirit, you are a sinner who is destined to go to hell. We should thus be all concerned about the gospel of the water and the Spirit that contains the righteousness of God.
If the Holy Spirit dwells in us, this means that we died to sin through our faith in the baptism of Christ. But our spirit is alive because of the newly attained righteousness. Moreover, on the day when our Lord comes again, our mortal bodies will receive life as well. This is why we must think about the One who has given us the Holy Spirit.
If you do not have the faith that believes in God’s righteousness, you do not belong to Christ. If, on the other hand, you do have this faith in God’s righteousness, the Spirit of God dwells in you. Without this faith, the Holy Spirit would not reign over you. Therefore, if you do not have the Word of redemption that contains the righteousness of God, you do not belong to Christ, even if you were to outwardly confess and recite the Apostles’ Creed in every Sunday service. If you do not belong to Christ, your spirit will be cursed and it will lead you to eternal destruction, no matter how much you might have wished to do good.