Babel or Babylon appears first in Genesis 11 as the site of the Tower of Babel, where human pride prompted God to confuse (balal) language. The name plays on the Hebrew balal (to confuse) while the Akkadian meaning is 'gate of god.' As a great empire, Babylon became the instrument of God's judgment on Judah and the paradigmatic symbol of worldly power arrayed against God.
Theologically, Babel/Babylon is the anti-Jerusalem — the city of human self-glorification as opposed to the city of God's glory. It recurs as a symbol in Revelation, where 'Babylon the Great' represents the entire system of godless empire and idolatry. The exile to Babylon and return from it mirrors death and resurrection, and serves as a template for eschatological redemption. God's people are called to come out of Babylon (Revelation 18:4).