1 Grk “I am already writing this [as] a second letter.” The object-complement construction is more smoothly rendered in English a bit differently. Further, although the present tense γράφω (graphō) is used here, English convention employs an epistolary past tense. (The Greek epistolary aorist might have been expected here, but it also occurs in situations unlike its English counterparts.)
2 The relative pronoun is plural, indicating that the following statement is true about both letters.
3 Or “I have stirred up, aroused.” The translation treats the present tense verb as a conative present.

In other versions

This is now the second letter that I am writing to you, beloved. In both of them I am stirring up your sincere mind by way of reminder,

Dear friends, this is now my second letter to you. I have written both of them as reminders to stimulate you to wholesome thinking.

Dear friends, this is now the second letter I have written to you; in both letters, I want to stir up your sincere understanding by way of reminder,

This is my second letter to you, dear friends, and in both of them I have tried to stimulate your wholesome thinking and refresh your memory.

Dear friends, this is already the second letter I am writing to you, in both of which I am attempting to stir up your sincere mind by a reminder,

This second epistle, beloved, I now write unto you; in both which I stir up your pure minds by way of remembrance:

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