When we consider the teaching of Scripture that the believer in Christ is sealed by the Spirit, it is well to notice first of all that our Lord Jesus Christ Himself was thus sealed:"Labor . . . for that meat which endureth unto everlasting life, which the Son of Man shall give unto you, for Him hath God the Father sealed" (John 6:27). This is the chapter in which Jesus speaks of Himself as the "Bread of God," "the Living Bread," and "the True Bread from heaven." This life-giving Bread came forth and was presented to men, as sealed by the Father, that they might eat and live forever. The sealing of the Son of Man was the Father owning Him as His well-beloved One, and declaring His delight in Him.
I heard an illustration recently that is relevant. Often today we find bread offered for sale with the maker’s name, or some trade name, either put upon it by a label or literally baked into it. The bread is sealed with the name of the baker. He practically says, "This bread is good. I put my name upon it, for I stand back of it in every particular." So has God the Father sealed the Bread from heaven. He acknowledged and approved His blessed Son in everything.
It is wonderful to learn from Scripture that the same Spirit who sealed the Saviour seals all who are saved by Him. In Eph. 1:13 the apostle addresses those who "trusted in Christ … in Whom also, after that ye believed, ye were sealed with that Holy Spirit of promise." In J. N. Darby’s version it is even clearer:"In whom also, having believed, ye have been sealed." How soul-assuring is this! Sealing is not a question of experience. It is a precious fact to be accepted on the authority of the Word of God. When you believed the gospel, dear saved one, you were sealed by the Spirit. God the Father put His stamp upon you, so to speak. He did this by giving you the Spirit to dwell in you_He who dwells in us is the seal.
In the same Epistle we read:"Grieve not the Holy Spirit of God, whereby ye are sealed unto the day of redemption" (Eph. 4:30). Does it say, "Sealed as long as you are faithful?" No, indeed, for if so, who could be sure of it from one day to another? Does it say, "Lest you grieve Him away?" No, not that either, for He is come to abide with and in us. We are sealed till "the day of redemption," that is, the day of Christ’s return when the redemption of our bodies will take place. Until that blessed consummation He never leaves the believer, neither in life nor in death.
I love to think of Him keeping guard over the very bodies of those who sleep in Jesus. The holy dead are not alone. "Precious in the sight of the Lord is the death of His saints" (Psa. 116:15). He never loses sight of one of them, and when the Lord returns He will give them resurrection life and escort them to the meeting place in the air.
But we must not overlook the admonition, "Grieve not the Holy Spirit." How may we grieve Him? By disobeying the Word. By indulging in any of the things mentioned in the preceding verses. Falsehood of the lips, dishonest practices, corrupt speech, bitterness, anger, clamor, railing, and malice_all these grieve the Spirit and hinder His ministry of grace in the life of the believer. To walk in the Spirit is to walk as before God, in lowliness and meekness, in purity and self-judgment, obeying the written Word, and thus doing His will from the heart. He who so walks does not grieve this holy, heavenly Guest, who has sealed us until the day of our triumph over death, when our descending Lord shall change our bodies of humiliation, making them like the body of His glory.
(From The Mission of the Holy Spirit.)