The Greek dynamis means power, might, ability, or miraculous power. It is the root of the English words 'dynamic' and 'dynamite'. In the New Testament, it primarily refers to the supernatural power of God operative in the world through the Holy Spirit.
Dynamis is the word Jesus used in Acts 1:8: 'you will receive dynamis when the Holy Spirit comes on you.' This is not mere information or good intentions — it is transforming, supernatural power for witness. Paul's entire apostolic ministry was grounded in dynamis (1 Corinthians 2:4–5: 'not with wise and persuasive words, but with a demonstration of the Spirit's power'). The gospel itself is 'the dynamis of God that brings salvation' (Romans 1:16). In the synoptic Gospels, dynameis (plural) refers to Jesus's miracles — powerful works that announce the Kingdom's arrival. The paradox of the cross is that divine dynamis works through apparent weakness (1 Corinthians 1:18; 2 Corinthians 12:9 — 'my power is made perfect in weakness').