'Spiritually' in the Bible

Yet we do speak wisdom among those spiritually mature [believers who have teachable hearts and a greater understanding]; but [it is a higher] wisdom not [the wisdom] of this present age nor of the rulers and leaders of this age, who are passing away;

But the natural [unbelieving] man does not accept the things [the teachings and revelations] of the Spirit of God, for they are foolishness [absurd and illogical] to him; and he is incapable of understanding them, because they are spiritually discerned and appreciated, [and he is unqualified to judge spiritual matters].