Seal of the Holy Spirit

== The Question & Premise ==
Ephesians 1:13 - "In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise, Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory."
What is the mechanics of this sealing and was there a duration for a specific purpose?  I propose to you that the sealing of the Holy Spirit was a particular event for a specific purpose and duration.  
In 2 Cor. 1:21-22, Paul writes "Now he which stablisheth us with you in Christ, and hath anointed us, is God; Who hath also sealed us, and given the earnest of the Spirit in our hearts."
== Definitions ==
=== Anointing ===
An anointing was a self-evident mark of assignment to a specific task/office/service.  This particular anointing was a supernatural endowment (gift) to authenticate the appointment to that task/office/service.
Exodus 28:41 - "And thou shalt put them upon Aaron thy brother, and his sons with him; and shalt anoint them, and consecrate them, and sanctify them, that they may minister unto me in the priest's office."
1 Samuel 16:13 - "Then Samuel took the horn of oil, and anointed him in the midst of his brethren: and the Spirit of the Lord came upon David from that day forward. So Samuel rose up, and went to Ramah."
John 12:3 - "Then took Mary a pound of ointment of spikenard, very costly, and anointed the feet of Jesus, and wiped his feet with her hair: and the house was filled with the odour of the ointment."
=== Seal ===
A seal is a visible mark used to authenticate or prove the authority of a message (e.g. a signet ring's mark on a letter).  Miraculous abilities through the Holy Spirit were the Divine “seal of approval” of God’s message to mankind.  To propose an interpretation of the “sealing” process in which one must use the Scriptures to prove that man has “the Holy Spirit” as a seal reverses the meaning of the word “seal.”  For example: the visible seal on an envelope proves the authenticity of the message inside; it is NOT the message that authenticates the seal.
Biblical examples of seals:
1 Kings 21:8 - "So she wrote letters in Ahab's name, and sealed them with his seal, and sent the letters unto the elders and to the nobles that were in his city, dwelling with Naboth."
Esther 3:12 - "Then were the king's scribes called on the thirteenth day of the first month, and there was written according to all that Haman had commanded unto the king's lieutenants, and to the governors that were over every province, and to the rulers of every people of every province according to the writing thereof, and to every people after their language; in the name of king Ahasuerus was it written, and sealed with the king's ring."
Matthew 27:66 - "So they went, and made the sepulchre sure, sealing the stone, and setting a watch."
Romans 4:11 - "And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also:"
Revelation 5:1 - "And I saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals."
=== Earnest ===
An earnest is a pledge or down payment. The earnest is the tangible, discernible evidence of other things to come.  The earnest must be self-evident, i.e., not dependent on other witnesses to prove its existence or validity, because it is the proof of other things. Paul told the Corinthians that God gave “us” (those with miraculous abilities) the earnest of the Spirit in our hearts.  
Some view the word “heart” in this verse as supporting the view that the Holy Spirit Himself literally dwells in the hearts of all Christians. But, “heart” is clearly figurative. God has shone in our hearts to give the light of the knowledge of the glory of God (2 Cor 4:4-6), the love of God has been poured out in our hearts (Rom 5:5) The evidence goes into man’s intellectual capability (mind/heart). There cannot be a literal dwelling in a figurative place.
== Purpose and Duration ==
God established His messengers with:
An anointing, a seal, and an earnest
All three terms refer to proofs that could be discerned through the senses.
The miraculous abilities provided that confirming proof of God’s message.
(Eph 1:13 KJV)  "...after that ye believed, ye were sealed with that holy Spirit of promise,"
In Acts 19:1-7, twelve Ephesians were given the miraculous gifts AFTER they were baptized. (Acts 19:5-6)  "they were baptized in the name of the Lord Jesus.  And when Paul had laid hands on them, the Holy Spirit came upon them, and they spoke with tongues and prophesied."  The “sealing” of the Ephesians occurred after, not when they believed.  The sequence of events is important.  This “sealing” cannot be something that the Ephesians (or all Christians) receive WHEN they are baptized.
It is something (miraculous abilities) that the Ephesians received AFTER they were baptized (when an Apostle’s hands were laid on them).
So the purpose of the Holy Spirit was to confirm through miracles that those who were speaking, revealing the NT to the world, were doing so with God's authority.  The duration of this was until that Word, that gospel, that New Testament was fully revealed or delivered to mankind (toward the end of the first century - 1 Cor. 13).  The mechanics of the sealing then was the direct immersion in the Holy Spirit of the Apostles (Acts 2; Paul) who then laid their hands on people after they had been immersed into Christ (Acts 8; Acts 19).  The earnest was toward the complete establishment of the church, the completion of the redemption of The Body not individual bodies.  Note that in Romans 8:23 Paul writes that they waited for the redemption of "our (plural) body (singular)" not "our bodies".
== Applications ==
There are several applications that can be made from this understanding of what the scriptures teach about the nature and duration of the seal of the Holy Spirit.
First, it means that this sealing and immediate indwelling was of a temporary nature and is not something that should be looked for or sought after in modern times just as miracles themselves should not be. It also means that those who claim such an indwelling must be able to show evidence of that indwelling and none of them can.
Second, it puts to rest the idea that the Holy Spirit guides us supernaturally in our understanding of scripture. Those who misapply John 14-17 universally instead of just to the Apostles claim that the Holy Spirit guides all Christians into all truth. This is not only not true, it rejects the purpose and power of the Bible itself. 2 Peter 1:3 says that they had already been given all truth. Jude 3 says that the mission was accomplished, that The Faith was once and for all delivered to the saints. There isn't any more truth to be guided to. The Bible is all-sufficient (2 Tim. 3:16-17) and we must exert our free will to study and rightly understand it (2 Tim. 2:15) and let it do the convincing (Rom. 10:17) and saving (Rom. 1:16; James 1:21).
Finally, it means that denominational doctrines like the argument for Once Saved Always Saved from the seal of the Holy Spirit are invalid because they do not correctly identify the nature and purpose of the seal.
In Truth and Love.