It's a minor point, two personal pronouns and the decision to capitalise them. By capitalising 'He' the implication is that of deity while the Greek text is ambiguous.
2 Thessalonians 2.7 reads:
For the mystery of lawlessness is already at work; only He who now restrains will do so until He is taken out of the way.
The decision to capitalise 'He' immediately tells me there was likely a Dispensationalist influence at work in the translation committee.
Historically Protestant groups before the Reformation as well as the majority of groups associated with Magisterial Reformation understood the 'man of sin' to be a reference to the Papacy. The popes are the man of sin sitting in the Temple of God which in the New Testament is identified as the Church of Jesus Christ. It is the claims to deity and miraculous power that so easily identified the Papacy in this view. Others like Petr Chelcicky would expand this concept and include not only the Papacy in the imagery but Christendom itself, a point of view I would also argue from the book of Revelation.
Under this view the mysterious restrainer is very likely Pagan Rome. It is Pagan Rome that holds back this antichrist (in place of Christ) spirit that fully becomes manifest in the 4th century. The mystery was already at work in the Church but the apostasy and wickedness were temporarily restrained. One thinks of the compromises already at work in the early Church, small groups of Christians joining the legions in the 2nd and 3rd centuries, the temptations toward respectability, the desire for buildings, ceremony, relics etc... These cancers would metastasise in the 4th century when the floodgates were opened and the definition of Christianity itself would change.
Others of historical and orthodox Protestant persuasion have in more recent years modified this view and believe the 'man of sin' to be something of a secular power. They believe the 'restrainer' is something associated with Christendom or perhaps the angel of Revelation 20 that binds Satan. They would view the unleashing of Satan as something akin to what we're seeing now, the fall of Christendom and the revival of paganism and the wickedness that goes with it.
There are some real strengths to this view but some other (hopefully obvious) deficiencies. I would be of the school that argues that Christendom itself is the manifestation of the Great Apostasy or 'falling away' and that passages like Revelation 11, 17 (and many others) help confirm that the great enemy of the True Church/Faithful Bride is the False Church/Harlot that masquerades as Jerusalem but is in fact Sodom. Identifying Mystery Babylon as Christendom itself, its fall is not the removal of holy restraint but a cause to rejoice (Rev 18.20).
Dispensationalism has a completely different take. This school which came to dominate American Evangelicalism has continued to change and shift many of its positions. Most of the theology once advocated by Dallas Theological Seminary and the Scofield Bible are no longer adhered to. And yet the fundamentals of the system remain and with it the eschatological scheme which is known even in pop culture through its science-fiction novels and movies.
Contrary to the New Testament, Dispensationalism insists that the Jews are the primary subject of God's historical plan. The Gentile Church represents a parenthesis that once removed will allow the primary plan, the Jews and the land of Israel to be re-activated as it were and become once more the focus of God's activity on earth. This system insists that God has two people, Jewish Israel and the Church which during its term is comprised of both Jews and Gentiles but is wholly separate from the nation of Israel. Dispensationalism insists the Church is a wholly separate organism and inherits no promises that belong to the Jews.
It's not my intention at this time to dismantle Dispensationalism but for unfamiliar readers I will simply say that Ephesians 2 plainly dispels this notion but Galatians and Hebrews contain major themes that completely destroy the foundations of this erroneous doctrine.
This school is also dominated by belief in the Pre-Tribulational Rapture, a doctrine which only appeared in the 19th century. This doctrine divides the Second Coming into two events. First they teach a 'rapture' in which Jesus comes and 'catches up' living believers and those in the grave into heaven. At this point a Seven Year Tribulation ensues. This is based on a reading of Daniel that is deeply problematic that is then imposed on the New Testament, especially the narrative in Revelation.
Finally we have the actual Second (Third?) Coming in which Jesus returns to earth and establishes a 1000 year literal physical Kingdom wherein Christ Himself sits on a literal throne in the city of Jerusalem.
Dispensationalism is rightly and properly called Dispensational Premillennialism and this must be distinguished from what is called Historical Premillennialism. The Historic position which goes back to the early Church digresses on two essential points. It does not have a rapture separated from the Second Coming and it rejects the notion that God has a separate plan for the Jewish Nation apart from the Church.
Some have erroneously argued that historically there was a concern for the Jews and Israel and this precedes the rise of Dispensationalism in the 19th century. They're both right and wrong. The interest found among Puritans and others for the Jews and a reconstitution of the nation of Israel was not rooted in the Dispensational notion that the Old Covenant is to be reactivated, the Temple rebuilt and that the New Covenant is a yet future reality to be fulfilled by the Jews during a Millennium.
Far from it. Their interest in the Jews and Israel was based on a belief that Romans 11 teaches a restoration of the Jews and a mass conversion to Christianity. They believed (and some still do) that this must occur before Christ returns. They read the 'and so' in Romans 11.26 as meaning 'and then', as a temporally successive event and take the 'all' to mean a literal 'all'.
I would argue with Calvin and others that they have misunderstood the nature of Paul's discussion on this point which began back in Romans 9, the key verse being 9.6 in which he explains the nature of Israel and then proceeds to explain God's plan regarding Jew and Gentile, the nature of God's redemptive-historical plan as well as His sovereign prerogative in how He has structured it. Therefore I would argue there are two possibilities with regard to Romans 11.26. One is that Paul is describing the manner in which the Jewish Remnant will be saved. The 'and so' is more or less 'and so in this manner', and has no reference to a succession of events. It would be a prophecy that would find its fulfillment throughout history and is not a sign we're waiting for.
Or, there is also the possibility that he's describing the True Spiritual Israel of Romans 9 and in his summary he's come full circle and is describing how in this manner all Israel both Jewish Remnant and Gentile will be saved. The number of Jews will be small but comprehensively the Church (both Jew and Gentile) is the True Israel of God.
Returning to the discussion at hand, Dispensationalism in making these foundational assumptions constructs a rather elaborate system that notoriously rips verses from context and reads its often obscure theological assumptions into texts in a fashion that sometimes overthrows their plain meaning or twists and contorts them in ways that can sometimes prove frustrating and baffling. Every nuance in the symbolism generates a new category of prophetic events to be fulfilled and thus Dispensationalism is dominated by a very convoluted scheme or multiple resurrections, comings, judgments, kingdoms etc...
The Scriptural narrative is actually fairly simple, Christ is coming, there will be a resurrection (unto life for some, death to others) and a final judgment. After this, eternal life and death. The Kingdom is heaven itself. Those who are born again by the Spirit participate in it now even while they still live in this age. In the resurrection, we will be found righteous, reconstituted and dwell in the heavenly fullness that we now experience in part.
In Dispensationalism's reading of Daniel 9 there's at least a 2000 year narrative gap between verses, though there's no reason to read it that way. The gap is imposed (eisegetically) by its other structural assumptions and with it comes a host of speculations about a 3rd Temple etc. These ideas are then imposed on other passages like 2 Thessalonians 2. It becomes rather fragile and has accurately been described as a house of cards. Once one is pulled out the whole system quickly implodes.
Dispensationalism has long argued the 'Man of Sin' in 2 Thessalonians arises during the Seven Year Tribulation which takes place after the Rapture. Of course this begs the question. To argue these secondary points becomes pointless unless you accept the idea of the Pre-Tribulational Rapture and the Seven Year Tribulation both of which are erroneous to begin with. Without these concepts their reading of 2 Thessalonians 2, along with the notion of a 3rd Temple collapses.
Thus assuming these positions they argue the Restrainer's removal must be related to the removing of the Church at the Rapture. Since the Holy Spirit was given in Acts 2 at the initiation of the Church (they argue) therefore when the Church is removed the Holy Spirit must also be removed. Thus the restrainer is the Holy Spirit and therefore in translation the pronoun 'he' is changed to 'He' to signify deity.
The text doesn't support it and I would argue it is also exegetically unsustainable as they are imposing a massive theological structure upon the 2 Thessalonians pericope.
The translators were really irresponsible on this point and mislead the reader who is not aware of the issues at hand.
One can embrace the error of Dispensationalism and still grasp the fundamentals of the gospel. Once can be a Dispensationalist and still be a Christian. That said the system itself is a perversion of Scriptural doctrine and its implications for both New Testament doctrine and ethics are widespread and very harmful. It is a poison and a cancer, a dangerous error that ultimately leads people away from the truth of Scripture and the focus on Christ. Thankfully it is so blatantly unsupported by the text that once exposed to alternatives a great number of people are beginning to abandon it. Even fifty years ago the Dispensational mainstream unable to withstand the unrelenting criticism of their system began its process of modification. And yet the eschatology now so deeply rooted in the Evangelical psyche continues to be retained.
I would argue Dispensationalism's main problem is that they are guilty of Judaising and absolutely refuse to accept what the Apostles teach in the New Testament. They refuse to accept the Apostolic interpretations of what the Old Testament and Israel were all about. The Dispensationalists have put a Christian gloss on the rejected doctrine of the Pharisees with regard to Israel the Messiah and the Jewish notion of a kingdom based on political dominion. This has reached its most egregious manifestation in recent years with the ascendancy of false teachers like John Hagee that quite literally teach that Jews are saved as Jews. They don't need to become Christians. This is actually worse than the Galatian error so emphatically condemned by the Apostle.
The implications of retaining the Pharisaical/Judaised expectation of the Kingdom are startling and it must be candidly observed that in embracing this error they have opened themselves to the very delusion spoken of in the 2 Thessalonians passage.