“…you were marked with the seal of the promised Holy Spirit; this is the pledge of our inheritance toward redemption as God’s own people, to the praise of His glory” (Eph. 1:13b-14).
According to the Apostle Paul, the experience of the “sealing with the Holy Spirit” is comparable to a “pledge.” It is something that takes place now in view of something greater to take place in the future. It is like a “down payment”, the full payment to be given at some point later on.
This means that our experience of the Holy Spirit in this life is not the whole story. It is only a part, perhaps a very small part, of the communion we will have with God in the future, when Jesus returns in His Kingdom. If God can seem far away in this life, in the next life He will fill all things, being “all in all,” as Paul says elsewhere (1 Cor. 15:28). If in this life we taste a bit of that joy and peace which result from the presence of the Holy Spirit (Gal. 5:22), then in the Kingdom every tear will be wiped from our eyes and we will know fullness of joy and pleasures forevermore at the right hand of God (Ps. 16:11).
There is a further point to be made here. The Holy Spirit is a “pledge” which we have from God, not from ourselves. We have not made a pledge to God, but rather He has made a pledge to us. This means that He is personally invested, we might say, in bringing us to that final state of perfection in His Kingdom. Once more, Paul emphasizes that salvation is the work of the Lord and not our own. If God pledges to save us by giving us the Holy Spirit, then we know that He will hold up His end of the bargain, so to speak, and do everything to finish what He began in us. The Apostle says this about Christ elsewhere: “I am confident of this, that the one who began a good work among you [viz., God] will bring it to completion by the day of Jesus Christ” (Phil. 1:6).
I think this gives us reason for confidence. If we have received the Holy Spirit, the we know that God has begun this work in us and that He will do whatever it takes to finish it. He opens our eyes to see the truth, He teaches us, He awakens our conscience when we sin, He gives us strength to repent of the evils we do, and He gives us graces and consolations to help us along the way. It is a work and a “responsibility,” so to speak, which He has taken upon Himself solely for His grace’s sake. He does not stand to gain anything from this, since of course God’s being is perfect in Himself and we cannot give Him anything; He would have created anything we give to Him, anyway. He saves us simply because He is good and He loves us; He saves us in order to do good to us, not to get anything from us.
But, as I emphasized in other points, I think it is also important to say that we must cooperate with this grace. I think Christian experience confirms this point. If you do not make an effort to cooperate with God’s grace, you will not find yourself carried aloft on the wings of eagles all the way into the Kingdom. On the contrary, if you are lazy or if you go into “auto-pilot,” you will soon find yourself in a state of spiritual slumber or even death, falling into sin subtly, without realizing it, and eventually you will be weakened in the face of strong temptations to grave sin. We must hold these two truths in balance — the objective truth of God’s providence and His grace, which begins a work and is able to complete it; the subjective truth of human freedom and the necessity of effort and struggle for righteousness.
But we should not struggle in the fear that God will leave us, or that we have to earn our way into heaven, or anything of that sort. On the contrary, salvation is always and entirely a work of grace. The fact that we have received the pledge of the Holy Spirit reminds us that salvation comes from God, that it is a gift, that it cannot be earned, and that, as far as God is concerned, we cannot disqualify ourselves from it, so long as we do not refuse it ourselves through a life of unrepentance. Our struggle is to cooperate with God who is attempting to free us from the bonds of sin and death; our struggle is to rise up from a fallen position, with God lifting us up and setting us on our feet. The analogy is imperfect, but I think the idea is clear enough. We struggle not to win God’s favor, but because that is how God helps us — respecting our freedom and calling upon us to participate in this deliverance ourselves.