Classical usage of the term σφραγίζω (to seal) essentially means to identify a belonging with its owner. ((Hoehner, 238)) In this sense a seal would be a mark denoting ownership of a particular object or thing. Previously in this passage, God has chosen a group of people and has predestined them for adoption. God’s mark of ownership of these people is the Holy Spirit ((Hoehner notes that many identify the Spirit’s act of sealing with baptism. He notes that this is a confusion of the ministries. Baptism refers to placing a believer in the body of Christ while sealing refers to God’s mark of ownership of a person.)). A second aspect of sealing is that of protection. Owners who mark their property will seek to protect what is theirs. O’Brien relates the relationship of the sealing of the Spirit with the promise of full possession of the inheritance: “by giving Gentile believers the Spirit, God ‘seals’ or stamps them as his own now, and he will be protect [sic] them through the trials and testings of this life until he takes final possession of them on ‘the day of redemption’” ((Peter T. O’Brien. The Letter to the Ephesians.(Grand Rapids: Wm. B. Eerdmans Publishing Co, 1999), 120.))
How does one receive the seal of the Spirit? The seal is not given because of some act done by a believer. Walvoord notes that the act of sealing is entirely accomplished by God. It is never commanded or set as a goal for believers to reach ((John Walvoord, 157)). However, the passage states that when the Ephesians heard the truth of the gospel and believed, they were sealed. The relationship between belief and sealing is not antecedent. The sealing occurs at the same time as belief and not some time after ((O’Brien, 119)).
Paul uses legal terminology to describe the relationship of the Holy Spirit to a believer. He is said to be the ‘guarantee’ of the believers inheritance. The term ἀρραβών (ernest [kjv]) is a Hebrew transliteration which literally means “an advance transaction that guarantees the validity of a contract or a full purchase price down payment, first installment, pledge” ((Timothy Friberg, Analytical Lexicon of the Greek New Testament, 75)) As Grudem describes it, “When God gave us the Holy Spirit within, he committed himself to give all the further blessings of eternal life and a great reward in heaven with him.” ((Wayne Grudem. Systematic Theology. (Grand Rapids: Zondervan, 1994), 791.)) The Holy Spirit is only part of God’s inheritance to believers. Romans gives a broader look at this picture by showing that believers have the firstfruits of the Spirit and eagerly await for the final stage of salvation: the redemption of the body (Rom. 8:23). This is the inheritance of which the Holy Spirit is the first down payment ((Millard J. Erikson. Christian Theology. (Grand Rapids: Baker Academic, 1998), 1010.)).
While the believer is sealed by the Spirit and marked out as God’s possession, believers can also grieve that same Spirit (4:30). The imperative found in this verse give ample motivation for the preceding and following imperatives (“Let the thief no longer steal…[4:28]” , “Let no corrupting talk come out of your mouths…[4:29]” , “Let all bitterness… be put away from you [4:31]” , “Be kind … [4:32]” , “Be imitators of God [5:1]” , “walk in love [5:2]”). This reference to irritating the Holy Spirit by these acts can possibly be traced back to Isaiah 63. Israel had rebelled and grieved the Holy Spirit in spite of all the blessings they had received ((God bringing up the children of Israel from Egypt comes to mind. Isaiah in 1-6 recounts that God desired to help, but no one available.)). It might be said that “Paul issues a warning to this new community [the church] not to grieve the Holy Spirit of God, ‘as Israel had done’ in the wilderness (cf. 1 Cor. 10:1-11), the more so since they have been sealed by that same Holy Spirit until the day of redemption (4:30) ((O’Brien, 347)).
The last phrase in 4:30, “by whom you were sealed for the day of redemption” might suggest purpose, but a reference to time might be more in view ((Hoehner, 632. )). The two are closely related. Certainly a purpose of the day of redemption includes a time principle. However, Hoehner suggests that two phases of redemption exist. One is the day “that sets believers free from sin” and a second that “occurs in the eschatological future when Christ comes for the saints, setting believers free from the presence of sin.” ((Ibid.)) Whenever the day of redemption is to occur, believers have been sealed and will experience the fullness of God’s intention for them.