[pjr12345]

Yes, and Peter warns them 17 beware lest you also fall from your own steadfastness, being led away with the error of the wicked; 18 but grow in the grace and knowledge of our Lord and Savior Jesus Christ.

I don't see where he encourages them to do anything but grow in their knowledge - perhaps to be less untaught and unstable. Also, I don't see where he directed them to lean on the understanding of non-Inspired writers, quite the contrary.

[Campion]

Also, I don't see where he directed them to lean on the understanding of non-Inspired writers, quite the contrary.

Both he and Peter appointed and ordained bishops to follow in their footsteps. Those bishops preached, taught, and wrote. Christians were expected to listen to them and be obedient to them.

Please look at 2 Tm 2:2 and Hebrews 13:17, both of which clearly speak to the appointment and authority of "non-inspired" church leadership.