4 Grk “to remember.” “I want you” is supplied to smooth out the English. The Greek infinitive is subordinate to the previous clause.
5 “Both” is not in Greek; it is supplied to show more clearly that there are two objects of the infinitive “to remember”—predictions and commandment.
6 Grk “words.” In conjunction with πρόειπον (proeipon), however, the meaning of the construction is that the prophets uttered prophecies.
7 Holy prophets … apostles. The first chapter demonstrated that the OT prophets were trustworthy guides (1:19–21) and that the NT apostles were also authoritative (1:16–18). Now, using the same catch phrase found in the Greek text of 1:20 (τοῦτο πρῶτον γινώσκοντες, touto prōton ginōskontes), Peter points to specific prophecies of the prophets as an argument against the false teachers.

In other versions

that you should remember the predictions of the holy prophets and the commandment of the Lord and Savior through your apostles,

I want you to recall the words spoken in the past by the holy prophets and the command given by our Lord and Savior through your apostles.

so that you recall the words previously spoken by the holy prophets and the command of our Lord and Savior given through your apostles.

I want you to remember what the holy prophets said long ago and what our Lord and Savior commanded through your apostles.

to remember the words proclaimed beforehand by the holy prophets and the commandment of the Lord and Savior through your apostles,

That ye may be mindful of the words which were spoken before by the holy prophets, and of the commandment of us the apostles of the Lord and Saviour:

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