The Hebrew word Tsiyyon (צִיּוֹן) refers to the hill in Jerusalem where David established his city and where Solomon's temple stood. It means 'citadel,' 'signpost,' or 'parched place.' It appears over 150 times in the OT and becomes a theological symbol for God's dwelling place and the heavenly city.
Tsiyyon began as a Jebusite fortress that David captured (2 Samuel 5:7) and became 'the City of David.' When Solomon built the temple on the adjacent hill (Mount Moriah), the name Zion expanded to encompass the entire sacred city — and ultimately the spiritual community of God's people. The Psalms of Zion (46, 48, 84, 87, 122) celebrate God's dwelling on the holy mountain. Isaiah prophesies that from Zion the law will go out and the word of the LORD from Jerusalem (Isaiah 2:3). The New Testament transforms Zion into an eschatological reality: 'You have come to Mount Zion, to the city of the living God, the heavenly Jerusalem' (Hebrews 12:22). Revelation's New Jerusalem is the ultimate Zion — God's dwelling with humanity forever.