'The Twelve' in the Bible

It had a massive and high wall, with twelve [large] gates, and at the gates [were stationed] twelve angels; and on the gates the names of the twelve tribes of the sons of Israel were written.

And the wall of the city had twelve foundation stones, and on them the twelve names of the twelve apostles of the Lamb (Christ).

And the twelve gates were twelve pearls; each separate gate was of one single pearl. And the street (broad way) of the city was pure gold, like transparent crystal.