The Lord may refer either to God or to Christ, but in the context of this whole passage it may be best to take Lord in these three verses as referring to God.

Slow comes from a verb that can mean “to delay,” “to linger,” “to be slack,” “to be late,” especially in reference to a designated or determined time. What is being denied here is the allegation of some people that God is slow about his promise, that is, he is negligent in fulfilling his promise at the appointed time. Promise ties this statement to the question in verse 4. Apparently the delay of the Parousia had been interpreted to mean that God was either indifferent or powerless to fulfill what he had promised. The phrase not slow about his promise may also be rendered as “not negligent (or, slow) in making what he promised to do happen.” As some count slowness can be expanded in translation; for example, “as some people think…” or “as some people think slowness means.”

Peter accepts that there is some delay, but he says that the delay has a positive purpose. It shows first of all that God is forbearing. This word, sometimes rendered as “longsuffering” or “patient,” is that quality of God which allows him to be somewhat lenient with sinners, in the sense that he refrains from punishing them immediately, but instead gives then an opportunity to turn back from their sins and thus escape receiving the punishment they deserve. (See also how “God’s patience waited” in 1 Peter 3.20.) God’s patience is here made to relate directly to the readers of the letter: he is patient toward you. Forbearing is literally “long-souled” and may be translated idiomatically in some languages as “having a big heart” or “large-hearted.”

As the Revised Standard Version footnote shows, there is a textual problem here. Instead of the preposition toward (Greek eis), some manuscripts have “on account of” (Greek dia), which is reflected in some translations such as Moffatt “he is longsuffering for your sake.” The meaning is not all that different, since both single out the readers as the object of God’s patience, and both equally affirm that this is for their own benefit. Most modern translations follow the text reflected in Revised Standard Version and Good News Translation. You is strange in this context, since he has been speaking about others, especially scoffers; perhaps it is used here to indicate God’s great concern for the readers of the letter, but it is also possible that many of the readers have begun to succumb to the influence of the false teachers, and therefore would need sufficient time to renounce their heretical beliefs and ungodly practices. At any rate, the strangeness of you in this verse remains, and this has led to the change of you to “us” in some manuscripts, as the UBS Greek New Testament indicates (and see King James Version “is longsuffering to us-ward”). It is clear, however, from the conclusions of textual scholars, that the primary reading here is not “us” but you.

Related to God’s patience is his not wishing that any should perish. Wishing comes from a verb that means “to want,” “to desire,” “to will.” Perish is “be lost” (New English Bible) or “be destroyed” (Good News Translation) as a result of God’s judgment. The phrase not wishing that any should perish may be rendered in some languages as “not wanting anyone to receive destruction” or “not wanting anyone to suffer destruction.” Any emphasizes God’s encompassing desire to save people from punishment; he doesn’t want even one person to be destroyed. The last part of the verse expresses the same idea positively: as a patient God, he wants all to reach repentance, that is “to turn away from their sins” (Good News Translation). The term repentance includes the negative element of turning away from evil and the positive element of doing God’s will. Thus we may translate as “turn away from evil and follow God’s will,” or idiomatically as “change their hearts and return to God.”

An alternative translation model for this verse is:
• The Lord is not slow in making (or, causing) what he promised to do happen, as some people think slowness means (or, is). Instead, he is big-hearted toward you, because he doesn’t want anyone to suffer destruction, but wants all people to turn away from their sins and return to him.

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 .