There have been countless theories as to the identity of the angels to whom the letters in Revelation 2-3 appear to be addressed (2:1,8,12,18; 3:1,7,14). These are the most commonly noted.
1. A few have argued that the 'angel' is the 'pastor' of the church. Against this view are several points. First, it is contrary to the NT portrait of church structure. Nowhere in the NT is a single individual portrayed as exercising pastoral authority over a congregation. Rule by a plurality of elders is the standard NT perspective. Second, this view is historically anachronistic, for the existence of a single pastor/bishop was unknown until Ignatius (@ 110 a.d.). Third, the word 'angel' is used some 60x in Revelation and always means a supernatural or spiritual being. Fourth, the word 'angel' is nowhere else in the NT used to designate an ecclesiastical office. Fifth, we know from Acts 20 that the Ephesian church was ruled by a plurality of elders.
2. Some suggest that the 'angel' refers to a prophet or delegated representative of the church, i.e., someone who undertook the responsibility of maintaining communication with those outside the congregation. This would be an ambassador or secretary of sorts who handled correspondence, etc. Stress is thus placed on the literal meaning of the Greek term angelos = messenger (cf. Luke 9:52; James 2:25).
3. In 1:11 the letters are directed to 'the churches' (plural). So also at the end of each letter we read: 'Let him hear what the Spirit says to the churches.' Thus the Lord speaks to the whole church and not just to an 'angel'. This leads some to conclude that the angel is the church, i.e., a personification of the church. The Greek text would allow (but by no means require) this interpretation, being rendered, 'to the angel which is the church.'
4. Another theory is that the 'angel' of each church is its guardian angel. See Deut. 32:8 (LXX); Dan. 10:13; 12:1; Matt. 18:10; Heb. 1:14; Acts 12:15. This is certainly a more likely view than any of the preceding three.
5. Beasley-Murray contends that "the most plausible solution of the problem recognizes the Danielic background of angels assigned to nations, but sees them as akin to the Persian fravashis, i.e., heavenly counterparts of earthly individuals and communities. The angels of the churches are then heavenly counterparts of the earthly congregations. The idea is not to be literalized, as though John thought of congregations seated in heaven above, answering to their equivalents on earth below. We help ourselves if we think of them as existentially in heaven though living on earth. John writes to people who form very earthly communities, whose life is characterized by the failures and weakness to which any human organization is prone. But these communities have one feature which marks them off from all others on earth: they are in Jesus (v. 9), and so saints of the Most High, priests and kings with Christ to God, lights in the world through whom the Light of the world shines. It is because their determinative life is in Jesus that John writes to the 'angels' of the churches. Their earthly conduct is the reflection of their heavenly relationship" (69-70).
Beasley-Murray also points to the fact that in 1:20 the seven stars in Christ's right hand are said to represent the seven angels of the churches. In the ancient world the seven (then known) planets were a common symbol for sovereignty (Mercury, Venus, Mars, Jupiter, Saturn, the moon, and either Earth or the Sun). He says: "Even in John's day there were many who believed that the planets were gods, exercising a powerful and even fearful influence over the lives of men. From this it was an easy transition to make of them a symbol of the political power exercised by the Roman Caesars over the world, and in this sense the seven stars often occur on imperial coins. When John declares that the seven stars are in Christ's hand, he is claiming that the sovereignty over this world resides not in the Caesars of Rome but in the Lord of the Church. These seven stars he then defines as the angels of the churches. The purpose of John's prophecy, from its first page to its last, is to assure the saints of God that they are kings and priests to God through the redemptive grace of Christ. The purport of the symbolism of the seven stars = the angels of the churches is therefore plain: it declares that the sovereignty of this world belongs not to those who proudly claim to be the saviours and lords of men and who seek to crush the Church of Jesus. It belongs to the Christ of God and his people" (69-70).