The Hebrew verb tsaphah (צָפָה) means to watch, keep watch, observe carefully, or serve as a lookout or watchman. It appears about 37 times in the OT, often in prophetic and military contexts.
The tsopheh (watchman) was a crucial figure in ancient Israel — stationed on city walls or hilltops to warn of approaching danger. This role became one of the most powerful metaphors for the prophet. God appointed Ezekiel as a tsopheh for the house of Israel (Ezekiel 3:17; 33:7): 'I have made you a watchman.' The watchman who fails to warn the people bears their blood-guilt. Habakkuk stood at his watch-post to hear from God (Habakkuk 2:1). Isaiah anticipates a day when watchmen will lift their voices together and shout for joy (Isaiah 52:8) at the sight of the LORD's return to Zion. The New Testament calls all believers to be alert — the watchman theology continues in Christ's admonitions to watch and be ready.