As we have noted, the epistles of Ignatius have two different versions (and in some cases, three). We will be primarily looking at the shorter versions, which are generally regarded as the originals. We have three English translations available on the web: Roberts-Donaldson, Lightfoot, and Hoole. For the Greek text, go here (it has the Perseus morphology!) and here for the PG (starts on column 661-662).
The purpose of this letter is primarily encouragement. The keyword in chapter 1 is “commend:” he commends the churches to the care of Jesus Christ. As with the letter to the Ephesians, Ignatius encourages the Magnesians to obey their bishop. In the case of the Magnesians, the youth of the bishop was apparently an obstacle to respect. It should not be, as Paul says in 1 Timothy 4:12 (quoted in the longer version). There will be those that try to stir things up in a negative way (chapters 4-5). The church needs to be aware of them, and strive instead for harmony (chapters 6-7). Chapter 8 is the usual warning against false doctrine. We should live for Christ, and beware of what he calls “Judaizing” (chapter 10). Ignatius evidences great humility by asserting the superiority of the recipients to himself (chapter 12). The final part of the letter is another exhortation to unity based on the truth (no non-doctrinal unity asserted here! Big-tent Presbyterians take note that Ignatius believes in unity around the truth, not unity in spite of truth, or ignoring the truth).
Here is a taste of his own words. He compares believers and unbelievers to two different kinds of coins: “For as there are two kinds of coins, the one of God, the other of the world, and each of these has its special character stamped upon it, [so it is also here.] The unbelieving are of this world; but the believing have, in love, the character of God the Father by Jesus Christ, by whom, if we are not in readiness to die into His passion, His life is not in us” (chapter 5).
One thing is rather unclear (and I am not the only one to notice this). At the end of chapter 6, he says, “Let nothing exist among you that may divide you; but be ye united with your bishop, and those that preside over, as a type and evidence of your immortality.” We can, of course, understand the commands to avoid division, and to be united with the bishop. However, what do those things have to do with being a type and evidence of immortality? The original Greek might point in a different direction. Instead of “immortality,” it can be translated “incorruption.” Hoole translates it this way, as does Lightfoot. The meaning then might run this way: avoiding divisive doctrines, and instead being of one mind with the bishop is a type and evidence of incorruptibility. This makes a bit more sense to me than translating the word “immortality.”
One last word on the study of doctrine. He commands all the Magnesians to “Study, therefore, to be established in the doctrines of the Lord and the apostles” (chapter 13). In the context, it is clear that this would be an example of humility (chapter 12), as well as staying in fellowship with the bishop (the rest of chapter 13). This is certainly a vote of confidence in the theological orthodoxy of the bishop. But the point I wish to make is that the doctrines of the Lord and the apostles are the proper study of the people of God.