Passage
On [the] east three gates; and on [the] north three gates; and on [the] south three gates; and on [the] west three gates.
On [the] east three gates; and on [the] north three gates; and on [the] south three gates; and on [the] west three gates.
Revelation 21:11 having the glory of God. Her shining [was] like a most precious stone, as a crystal-like jasper stone;
Revelation 21:12 having a great and high wall; having twelve gates, and at the gates twelve angels, and names inscribed, which are those of the twelve tribes of [the] sons of Israel.
Revelation 21:13 On [the] east three gates; and on [the] north three gates; and on [the] south three gates; and on [the] west three gates.
Revelation 21:14 And the wall of the city had twelve foundations, and on them twelve names of the twelve apostles of the Lamb.
Revelation 21:15 And he that spoke with me had a golden reed [as] a measure, that he might measure the city, and its gates, and its wall.
The verse centers on "east", "three", "gates", "north", and "south". It is saying that the verse draws attention to "east" and "three", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 12's "having a great and high wall having..." into verse 14's "And the wall of the city had...", so "east" and "three" belong inside that flow. In Revelation context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "east" and "three" with trust shaped by these words, not by a vague optimism outside the passage.