39 It could be argued (1) that the ὅτι (hoti) at the beginning of 3:11 is grammatically subordinate to the preceding statement at the end of 3:10. As §456.1 points out, however, “Subordination with ὅτι and διότι is often very loose … and must be translated ‘for.’ ” Thus (2) ὅτι assumes an inferential sense, standing at the beginning of a new sentence and drawing an inference based upon all that has preceded. This is confirmed by the structural parallel between the present verse and 1:5.
40 The word “gospel” is not in the Greek text but is supplied to clarify the meaning. See the notes on the words “gospel” and “message” in .
41 See the note on the word “message” in , where this same phrase occurs.
42 For this is the gospel message … that we should love one another. The structure of this verse is parallel to 1:5, indicating the beginning of a second major section of the letter.

In other versions

For this is the message that you have heard from the beginning, that we should love one another.

For this is the message you heard from the beginning: We should love one another.

For this is the message you have heard from the beginning: We should love one another,

This is the message you have heard from the beginning: We should love one another.

For this is the message that you have heard from the beginning: that we should love one another,

For this is the message that ye heard from the beginning, that we should love one another.

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