From eu ('well') and sebomai ('to worship/revere'). Eusebes means one who worships well โ genuinely devout, showing practical reverence toward God. It is the Greek equivalent of the Hebrew chasid (H2623).
Eusebeia (the noun form, G2150) is one of the Pastoral Epistles' key terms. Paul commands Timothy that bodily training has some value, but eusebeia is profitable for all things, holding promise for both this life and the life to come (1 Tim. 4:7โ8). Cornelius (Acts 10:2) was the archetypal eusebes โ devout, generous, prayerful. But true eusebeia is not external religion but the inner transformation that expresses itself in reverent living. Peter uses the Sodomites' destruction as a contrast to save 'the godly (eusebes) out of temptation' (2 Pet. 2:9).