This verse goes back to the subject of the second coming of Christ, which was first mentioned in 1.16 but which has been interrupted by the lengthy discussion regarding the false teachers.
First of all is a way of expressing priority and importance, hence “above all.” The use of First may present a problem in translation, especially in languages that require a second point if a first point is mentioned. In such cases a natural way of expressing priority should be used without necessarily mentioning a number. See comments on 1.20, where the same phrase occurs, for other translation models.
For you must understand this, see comments on 1.20. It is not clear in the Greek text if what follows is intended to be part of the prophetic message and of the Lord’s teachings, all of which the readers have just been told to remember; however, the context seems to indicate that this is the case. In the last days is equivalent to “In the last time” in Jude 18, for which see discussion there. The expression in the last days is actually the more familiar one and is used frequently in the Greek translation of the Old Testament, the Septuagint (see Gen 49.1; Jer 30.24 [37.24 in the Septuagint]; Dan 2.28; Hos 3.5; Micah 4.1) and in many writings during the period after the apostles.
One of the features of the last days is the appearance of people who make fun of God’s message. For scoffers see also comments on Jude 18. The two verses are very similar, with these differences: Jude has only “scoffers following,” while 2 Peter has scoffers will come … with scoffing, following …; and 2 Peter has passions while Jude has “ungodly passions.” The emphasis of both statements is that the scoffers are following their own will and not God’s. It is not clear whether these scoffers are the same people as the false teachers in chapter 2, but it makes sense to understand the two groups as one and the same. Scoffing is the action that scoffers do; its double use here, scoffers … with scoffing, is perhaps a form of Hebrew idiom signifying intensity or emphasis. In some cases the two terms can be combined into one to produce a more natural translation; for example, “they will mock you,” or Good News Translation “they will make fun of you,” and New English Bible “men who scoff at religion.” Other ways to translate scoffing are “making jokes about” or “laughing at.” The mocking statements are found in verse 4, and for this reason it is desirable to put “mock” right before that verse.
An alternative translation model for this verse is:
• The most important thing is that you understand that in the days just before the end time, some people will appear whose lives are controlled by their own lusts (or, evil desires). They will mock you by saying …
Quoted with permission from Arichea, Daniel C. and Nida, Eugene A. A Handbook on The Second Letter from Peter. (UBS Handbook Series). New York: UBS, 1980. For this and other handbooks for translators see here .
