This is a picture used to communicate a message. For instance, the people of God will NOT be walking on literal streets of gold. The city is an image, a picture, of the people of God (the wife of Christ) and not a destination.
The wall of jasper is emblematic of sacrifice (bloody sacrifice). The city pure gold speaks of the divinity of the wife of Christ, as they will be like Him and share in His substance. Clear as glass speaks of the absence of impurity.
The Foundations speak of honor and glory of the Apostles’ faith upon which the city rests. The gates being pearls speaks of the gentile believers though which all must enter. The street, or wide-open space, speaks of a large gathering place for all who want to know Jesus, and its transparency speaks of the lack of imperfection in the true bondservants of Jesus Christ.
