The Greek adjective biaios means 'violent,' 'forceful,' or 'mighty.' It derives from bia ('force, violence') and describes something of overwhelming power or forceful intensity. It appears once in the New Testament, in Acts 2:2, in the description of the day of Pentecost.
Acts 2:2 describes the coming of the Holy Spirit at Pentecost as 'a sound like the blowing of a violent wind (pnoēs biaias) came from heaven.' The word biaios emphasizes the overwhelming, irresistible force of the Spirit's arrival — not a gentle breeze but a mighty, powerful wind.
This language echoes the Old Testament imagery of the divine wind (ruach) and its creative and prophetic power (Genesis 1:2; Ezekiel 37:9). At Pentecost, the new creation has arrived — the Spirit poured out on all flesh as Joel prophesied. The force of the Spirit's coming signals the inaugurated power of the new age.