Problem: Christian commentators are greatly confused over the identity of the restrainer. Who exactly is the restrainer?
Solution: Many views have been offered. There are multiple characteristics of the restrainer that need to be considered: First, the restrainer is currently holding back evil. Second, the restrainer is described with both masculine and neuter pronouns. Third, the restrainer will be removed before the end of history. Fourth, Paul speaks of the restrainer with cryptic terms. With these criteria in mind, let’s consider the alternate views.
INTERPRETATION #1: The restrainer is the Roman government.
Most of the church fathers held to this view. Under this view, Paul didn’t want to say this outright, because this would have led to persecution for the Church in the first century. On this view, the masculine singular (“he”) would refer to the Roman emperor, while the neuter pronoun (“what”) would refer to the Roman government.
For instance, Preterist Gary DeMar holds that this passage likely refers to the Roman Empire, while the restrainer might refer to King Agrippa, who stopped further killing of Christians after the death of James and tried to stop the Jewish War in AD 66.
However, we do not hold to this view. For one, the Roman Empire did not “restrain” the Antichrist. Specifically, under the Preterist view, Emperor Nero was the Antichrist, and he governed over the Roman Empire! Moreover, King Agrippa did not restrain Nero in any way.
Second, Daniel and Revelation see human government as pushing for the rise of the Antichrist—not restraining him.
Third, the Roman Empire fell in the fifth century AD, so this “restrainer” would have no meaning for today. As Thomas writes, “Elimination of this solution is sealed when we remember that the Roman Empire has long since ceased to exist, and the appearance of Christ or the lawless one has yet to take place.”
INTERPRETATION #2: The restrainer is the preaching of the gospel.
Romans 1:16-17 describes the gospel as the power of God (see also 1 Thess. 1:5; 1 Cor. 1:18, 24; Heb. 4:12; Mt. 4:1-11). Under this view, the restrainer is the active preaching of the gospel, which will end before the end of human history (Mt. 24:14). On this view, the masculine restrainer is Paul the apostle, and the neuter restraint is his ministry of preaching.
However, we do not hold to this view either. This would place Paul himself at the center of eschatology, which seems to be a bizarre reading. This would also mean that the “restrainer” (i.e. Paul) has been gone for almost 2,000 years without the appearance of the Antichrist. Furthermore, why would Paul speak of himself in the third person (“he who now restrains”), rather than the first person (“I who now restrain”)?
INTERPRETATION #3: The restrainer is Satan, restraining the Antichrist.
Under this view, Satan is holding back the Antichrist from coming into power until the time is ready. Since Satan could have an Antichrist prepared in any time (1 Jn. 2:18), this view argues that Satan is the one restraining the Antichrist from being revealed prematurely.
This view has some plausibility, yet we do not hold to it. For one, it doesn’t adequately answer the shift of the pronoun from the neuter to the masculine singular. Furthermore, Satan is not “taken out of the way” during this time. The very next verse says that the Antichrist will come “in accord with the activity of Satan, with all power and signs and false wonders” (v.9).
INTERPRETATION #4: The restrainer is the Holy Spirit, indwelling the Church.
This view was held by some early church fathers. Jesus said that the Holy Spirit would convict the world of sin, unrighteousness, and judgment (Jn. 16:8-11). With the Holy Spirit removed, this would lead to utter lawlessness. This would make sense of the switch from the neuter pronoun (“what”) to the masculine pronoun (“he”). After all, the Holy Spirit is sometimes described in the neuter (Jn. 14:26; 15:26; 16:13-14), while he is also described in the masculine singular (“he”). Moreover, if the restrainer is really holding back the power of Satan (v.9), then an omnipotent God would be required.
If the Church is rescued before the Tribulation, then all those indwelt by the Holy Spirit would be “taken out of the way” (v.7). Believers are the “light of the world” (Mt. 5:14), and without them, we could very easily see the Antichrist rise to power.
This does not mean that the Holy Spirit is inactive during the Tribulation. Certainly, he is (Joel 2:28-3:1). Instead, this means that the Holy Spirit is simply taking on another role. Thomas writes, “The special presence of the Spirit as the indweller of saints will terminate abruptly at the parousia as it began abruptly at Pentecost. Once the body of Christ has been caught away to heaven, the Spirit’s ministry will revert back to what he did for believers during the OT period.”
 See footnote. Charles Powell “The Identity of the ‘Restrainer’ in 2 Thessalonians 2:6-7” Bibliotheca Sacra 154 (July-September 1997): 328.
 DeMar is not dogmatic on King Agrippa being the restrainer. This is only his “opinion,” as he puts it. DeMar, Gary. Last Days Madness. Atlanta, GA: American Vision, 1999. 303-306.
 Thomas, R. L. (1981). 2 Thessalonians. In F. E. Gaebelein (Ed.), The Expositor’s Bible Commentary: Ephesians through Philemon (Vol. 11, p. 324). Grand Rapids, MI: Zondervan Publishing House.
 See Stott, John R. W. The Message of Thessalonians: The Gospel & the End of Time. Leicester, England: Inter-Varsity, 1994. 169.
 For an exposition of this view, see Dixon, Paul. “The Evil Restraint in 2 Thess 2:6.” JETS 33/4 (December 1990) 445-449.
 Charles Powell “The Identity of the ‘Restrainer’ in 2 Thessalonians 2:6-7” Bibliotheca Sacra 154 (July-September 1997): 329-330.
 Thomas, R. L. (1981). 2 Thessalonians. In F. E. Gaebelein (Ed.), The Expositor’s Bible Commentary: Ephesians through Philemon (Vol. 11, pp. 324–325). Grand Rapids, MI: Zondervan Publishing House.
“And now ye know what withholdeth that he might be revealed in his time. For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way.(2 Thess 2:6-7)”