An exclamation or interjection expressing sudden emotion—surprise, recognition, fear, or protest. In Luke 4:34, the demon-possessed man cries out 'Ha! What have we to do with You, Jesus of Nazareth?' The particle often introduces a challenge or expresses alarm. It's the verbal equivalent of a startled reaction. Demonic spirits frequently use it in the Gospels when confronted by Jesus—recognizing His identity and authority while protesting His interference. It's an involuntary outburst revealing inner disturbance.