Epigeios means 'upon the earth' or 'earthly' — that which belongs to the realm of the earth as opposed to heaven. It can describe physical things (earthly bodies, earthly tabernacles) and spiritual attitudes (earthly wisdom, earthly concerns). It appears in key Pauline passages contrasting earthly and heavenly realities.
Paul's theology presents a fundamental tension: believers are citizens of heaven (Philippians 3:20) yet living in earthly bodies (epigeios) — the 'tent' of 2 Corinthians 5:1. The Christian life is characterized by this dual citizenship. Those who are 'enemies of the cross' are those whose 'mind is on earthly things [epigeios]' (Phil 3:19) — they are controlled by what is temporary rather than eternal. James 3:15 distinguishes wisdom: earthly/natural/demonic wisdom vs. wisdom from above. The resurrection hope transforms the epigeios: the humble earthly body will be transformed into a heavenly body (1 Cor 15:40).