In the previous verses paul described in vivid terms and elaborate detail the sorts of depravity which comes upon all those who suppress the truth of God.
Paul anticipates that the believer who peruses his list of depravities will assume to themselves that he is talking about the plight of the unbeliever. But Paul makes it clear that the sinful practices of the previous chapter do not apply solely to unbelievers, but to every human. For this reason no one has cause to pass judgement upon his neighbor because all of humanity is guilty of suppressing the truth of God and thus subject to like sinful passions as every other human. The consequences our first parent’s rejection of God have been imputed to every human soul since.
Therefore we are not to make distinctions between ourselves and unbelievers. Though we are expected to make distinction between righteousness and sin. We are not to consider our neighbor as unworthy or more unworthy than ourselves. The person who does so will be condemned by God, the only righteous judge of men.