Charles Spurgeon Commentary 2 Peter 1:9

"For he that lacketh these things is blind, seeing only what is near, having forgotten the cleansing from his old sins." — 2 Peter 1:9 (ASV)

But he that lacketh these things is blind, and cannot see afar off,

He is short-sighted; he has some light, and some physical sight, but he cannot see far; spiritually, he is blind.

And has forgotten that he was purged from his old sins.

It is a great mercy not merely to see men as trees walking, but to have clear spiritual vision. There is a great deal of dust that gets into our eyes, and there is no way of clearing out that dust, and becoming long-sighted, getting a sight that can see to heaven, except by getting that spiritual life which manifests itself in faith, virtue, knowledge, temperance, patience, godliness, brotherly kindness, and love.