Its wall, a hundred and forty-four cubits: Good News Translation takes this distance (216 feet) to be the height of the wall (also New Jerusalem Bible, Revised English Bible, Bible en français courant, Phillips). It may, however, refer to its thickness (New International Version, Nova Tradução na Linguagem de Hoje). Some commentators make the point that, for a city that is 1,500 miles tall, a wall only 216 feet (66 meters) tall is so small that it seems foolish. But it is also pointed out that the wall, in this case, is not for the protection of the city (inasmuch as the gates stay open all the time) but for its demarcation. In any case, the notion of height is preferable to that of thickness. A translation should opt for one or the other; simply to say, as Revised Standard Version and others say, a hundred and forty-four cubits (or, 216 feet, or 66 meters), without indicating that this is the height, does not qualify as a translation. An alternative translation model is “He also determined the height (or, thickness) of the wall (or, fence). It was 216 feet (or, 66 meters).”
A man’s measure, that is, an angel’s: the meaning here is that the measurement used by the angel was the normal one used at that time; it was not a special angelic measurement. New Revised Standard Version now has “by human measurement, which the angel was using”; New American Bible, Revised “according to the standard unit of measurement the angel used”; New Jerusalem Bible “by human measurements.” Or the translation can be “according to the way people measure things.”
The purpose of the footnote at the end of verse 17 in Good News Translation is to allow the reader to appreciate the fact that the numbers 12,000 and 144, in verses 16 and 17, may have symbolic value, since they are both multiples of twelve (12 x 1000; 12 x 12), a number in the Bible that indicates completeness. This fact can be carried over into translation by using the biblical terms stadia and cubits; but neither of them, in English at least, is in current usage. But the two can be used, and in footnotes the modern equivalents may be given. One translation has tried to represent the text by saying “12,000 kilometers … 144 arm’s lengths” (an “arm’s length” in that language is a standard measure). This may be possible in other languages.
Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on The Revelation to John. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .