For this is love, that we follow his commandments, compare 1 John 5.3a. The first clause has also been rendered ‘love means (or consists in) this.’ The that clause states what exactly love means, or in what love consists. The term love is to be taken here in its widest range: love for God and for each other.
Follow his commandments in the Greek is literally “to walk in his commandments.” The expression refers to virtually the same thing as “to walk in truth” (verse 4). The rendering may closely resemble that of “to keep his commandments” in 1 John 2.3 (which see), or it may even be the same.
This is the commandment…, that you follow love is in the Greek literally “this is the commandment…, that in it you walk.” There is a certain parallelism between this sentence (verse 6b) and the preceding one (verse 6a), and the relationship between the two clauses in each sentence is the same. Verse 6b is ambiguous in two aspects: (1) The demonstrative this may point back to verse 6a (which in its turn explains the last clause of verse 5) or forward to the that clause of verse 6b. (2) In the Greek clause “in it you walk,” the pronoun “it” may refer to “commandment” (verse 6b) or to “love” (verse 6a).
Revised Standard Version, Good News Translation, and the majority of translators take this as pointing forward and interpret “in it you walk” as meaning “in love you walk”; hence, “you follow love.” Thus interpreted verse 6b is a reverse way of saying what is said in verse 6a. The statement serves to show that love and “God’s commandment” are virtually interchangeable; man can truly practice love only by doing what God has told him to do, and, conversely, what God always has told him to do is to love. This interpretation is based on, and does justice to, the parallelism existing between the two parts of verse 6.
The expression follow love, or “walk/live in love,” may have to be restructured. One may say, for example, ‘to live as people who love (God and their brothers),’ ‘to act as (or to do what) people who love (God and their brothers) ought to do.’
An objection against the interpretation of verse 6b just given is that in itself the Greek word order in the whole verse seems to suggest that “it” refers to commandment rather than to love. Some translators give a rendering along these lines; for example, “this is the command which was given you from the beginning, to be your rule of life” (New English Bible), ‘this now is the command which you received already in the very beginning, in order that you would really live in accordance with it.’ Such renderings are certainly possible and give to verse 6b a force which the verse lacks in the first-mentioned interpretation.
For as you have heard from the beginning see comments on 1 John 2.7. The clause is rather redundant after verse 5. This redundancy serves to stress the validity of the statement in which these words are embedded. The clause, again, has the character of a parenthetical statement and may better be transposed. It is often best rendered then as a full sentence at the end of the verse, ‘This is what you have heard from the beginning.’
Quoted with permission from Haas, C., de Jonge, M. and Swellengrebel, J.L. A Handbook on The Second Letter of John. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .