Quanbeck states, “Knowledge is one of the author's favorite words (1.2,3,5,6,8; 2:20; 3:18).” That makes exactly seven times in which it is used, the number 7 symbolically standing for perfection or completion.The contexts in which this word appears are also interesting to observe:
1:2 the knowledge of God and of Jesus our Lord
1:3 the knowledge of him who called us
1:5 supplement...virtue with knowledge
1:6 and knowledge with self-control
1:8 the knowledge of our Lord Jesus Christ
2:20 the knowledge of our Lord and Savior Jesus Christ
3:18 the knowledge of our Lord and Savior Jesus Christ
I have previously demonstrated that this set of seven plays an important part in defining the symmetrical organization of this epistle (see my post on “II Peter: Introduction to the Literary Structure.”)
Green explains that in the context of II Peter, true knowledge was different than what the false teachers claimed to have. “True knowledge of God and Christ produces grace and peace in the life; what is more, it produces holiness.”
There are two examples of symmetry in this listing. The first and last two occurrences act as an inclusio [a set of bookends] for the whole letter, as indicated by the reversed wording
“Jesus – Lord … Lord – Jesus.”
Next, note that the first two and last three in the series of seven concern the knowledge of Jesus, bracketing the two usages (1:6,8) in the center which do not specifically mention Him. However, as the footnote in the Jerusalem Bible points out, “All through this letter it is Christ who is proposed as the object of a Christian's knowledge.”
“Second Peter is characterized by an apocalyptic vision of this world as corrupt because of lust (1.4) and bound for destruction. It urges the reader to escape by means of the knowledge of Christ and of God and by earnest moral striving that is grounded in the promises and gifts of God. The goal is to participate in the divine nature and to enter the eternal kingdom (1.11).” (Tiller)
Reicke says, “The expression 'intimate knowledge' or 'adequate gnosis' appears repeatedly in the epistle. But the emphasis is not on the mystic experiences characteristic of Gnosticism, the representatives of which were proud of their 'gnosis' in the sense of ecstatic contact with eternity (cf. I Cor viii 1; II Cor xii 1-5). The author rather speaks polemically against the influence of Gnosticism (cf. Rev ii 14f.). Here it is a matter of continuously deepening knowledge of God's words in the plan of salvation, the life in Christ, and the eschatological hope. The believers were instructed in these subjects, when they were accepted into church fellowship, and it is now their responsibility to improve and apply their knowledge in these matters.”
Harvey also stresses the great importance of knowledge in this epistle, even labeling 1:3-21 “Life-Changing Knowledge of Jesus.” He goes on to say, “Peter's present boldness is the Holy Spirit inspiring him to strike a clear note as the theme of his letter: the Christian's ability by grace to discern between truth and falsehood, to endure hostility and persecution, and to live with hope and holiness while waiting for the 'new heaven and new earth,' all indeed realistic expectations because Christ has given everything we need to make these experiences happen.”
Payne says, “The message of the letter opens with a positive declaration of what God has given the Christian. Much of the phraseology of v. 3 recalls gnostic concepts and claims...against which Peter puts up the basic Christian truth that divine power, true knowledge (the Gk. word epignosis implies full knowledge), and all that stem from them, are the gifts of God, unmerited and but for His grace unattainable.”
“'Knowledge' [in 2 Peter 1:2]...implies an intimate and personal relationship. It is the means by which God's grace and peace may be received and experienced. Peter used this term epignosis again in 2 Peter 1:3, 8; and 2:20. The shorter form (gnosis) is found in 1:5-6 and 3:18. Christians are urged to take advantage of the 'full knowledge' available to them through Christ Jesus (each occurrence of epignosis in 2 Peter is related to Christ). In this way they could combat false teachers who claimed to have special knowledge (gnosis) but who openly practiced immorality (cf. Paul's usage of epignosis to combat incipient Gnosticism: Col. 1:9-10; 2:2; 3:10).” (Gangel)
Wheaton writes: “Knowledge is stressed here [i.e. 1:2] as the means by which grace and peace can be multiplied in the believer's life. The Gnostic deviationists exalted knowledge (Gk gnosis) as being superior to faith, and in reply orthodox writers stressed the importance for Christians to acquire epignosis, 'full knowledge', (as here) in order to combat this heresy. Such knowledge is never merely speculative, as was the Gnostic variety, but springs from a personal relationship with and experience of God in Jesus our Lord (cf. Jn. 17:3; Phil. 3:10).”
Schmitz: “The knowledge of God's truth is of equal importance with experiential profession of the Lord, and finally pushes it into the background. Hence, conversion to the Christian faith can be described almost technically as coming to a knowledge (epignosis) of the truth (2 Pet. 2:21, etc). In 2 Pet. epignosis is used in a similar theoretical, technical way in connection with God's call. Knowledge is here of the orthodox tradition, of the catholic [i.e. universal] doctrinal teaching (2 Pet. 1:2, 3, 8; 2:20) which, as in the Pastorals, must become effective in a corresponding manner of life. It is interesting that gnosis has a good sense in 2 Pet. (cf. 1:5f; 3:18). This does to apply to ch. 2, where an anti-gnostic writing (Jude) has been incorporated which uses only epignosis (2:20) and epiginosko (2:21).”
Considering the great emphasis on “knowledge” in this short epistle, as evidence by the above opinions, it is rather amazing that Neyrey in his commentary appears to go to great lengths to avoid mentioning this subject at all. Instead, he spends his time trying to defend his thesis that it was the Epicurean philosophy which Peter was countering instead of the Gnostics or proto-Gnostics. Thus, it is not surprising that in his discussion of 1:3-11, Neyrey carefully defines almost all of the key virtues listed there except for “knowledge,” presumably since that does not happen to fit into his overall thesis.