The first part of John’s long parenthesis, verses 12-17, was written to reassure his readers; for John did not want them to think that he was questioning their salvation. Rather, he has written to them because their sins have been forgiven and because they do know the Father. If they miss this truth, they have misunderstood him. On the other hand, John does not want them to think that what he has written regarding the tests of life has no relevance for Christians, for this would be a misunderstanding too. Thus he now goes on to show how what he has said should be applied to their lives. They are not to doubt their salvation, but rather, being assured of it, are to press on in those areas which give evidence of their transformation and which indeed bring the greatest measure of personal blessing. What is the Christian to do? Quite simply, he is to refuse to love the world and its values and instead love God and the will of God. In stating this, John also gives two reasons why this is the only sane course for any Christian.
John’s appeal to his readers is stated negatively, but the positive side must be understood also. Christians must not love the world. At the same time it must also be said that they are to love God and do His will. Indeed, it is only as the love of God fills them and the will of God motivates them that the world can be conquered, just as in the preceding verse it is only as the Word of God abides in them that Satan can be overcome.
With the exception of one passing reference in 2:9, this is the first time in the letter that John has used the word “world” (kosmos). But now it occurs six times in just these three verses, and it will occur many more times later on. On the whole, it is one of the most important terms in the Johannine vocabulary. What is the “world”? The answer to that question is a complex one, for the word itself has a wide range of meanings. At times, though this is a very minor usage, John seems to mean little more than the “universe,” as in John 1:10. This, of course, is the basic meaning of the Greek word. In the early history of the Greek language kosmos meant “an ornament” (this meaning is preserved in English in the word “cosmetic”), then later the “universe” or “world globe,” as the ornament of God. In this early period kosmos could also mean “that which is well assembled or constructed,” “well ordered,” or “beautiful.” In time the application of the word to the world led also to a further development by which it came to denote “the world of men.” This use is also present in John, occurring at times without apparent moral overtones. It is said of the world in this sense that God loved it and gave His only begotten Son for it (John 3:16), that it is the object of His saving purposes (John 3:17), that Jesus gave Himself as a propitiation for it (1 John 2:2), and that Christ is its Savior (John 4:42; 1 John 4:14). It must be understood of this use of the word that it refers to the human race collectively and not necessarily to each individual, otherwise the verses in question would imply a universal salvation of all men which is, however, repudiated elsewhere.
The third major use of the word is one which involves the ethical dimension; and it is not only the most common, it is also the most significant usage in John’s writings. The idea here is of the world of men in rebellion against God and therefore characterized by all that is in opposition to God. This is what we might call “the world system.” It involves the world’s values, pleasures, pastimes, and aspirations. John says of this world that the world lies in the grip of the evil one (1 John 5:19), that it rejected Jesus when He came (John 1:10), that it does not know Him (1 John 3:1), and, consequently, that it does not know and therefore also hates His followers (John 15:18-21; 17:14). It is in this sense that John speaks of the world in the passage before us.