2 Peter 1:12 states Peter's intent to remind — here in 3:1 he acts on that, stirring up by way of reminder.

2 Peter 1:13-15 uses the same 'stir up by way of reminder' language — Peter repeats his purpose for writing this second letter.

1 Peter 1:1 identifies the first letter Peter wrote to these same recipients, referenced here as 'the second letter'.

Revelation 3:3 commands 'Remember, then, what you received and heard' — a direct call to remember, matching Peter's purpose of stirring up by reminder.

1 Peter 1:2 is part of the first letter Peter mentions here as his earlier writing to them.