In the following passage (Eruvin 21a in William Davidson edition) the sages try to determine the size of the Torah scroll that Zachariah saw in his prophecy:
In order to determine the measure of God’s cubit, the Gemara cites a verse that describes the size of the span between God’s thumb and little finger (in a manner of speaking). And it is written: “Who has measured the waters in the hollow of His hand, and meted out heaven with the span, and comprehended the dust of the earth in a measure” (Isaiah 40:12). If the entire world measures one square span, which is a quarter of one square cubit, we find according to this calculation that the entire world is one part in three thousand and two hundred of the Torah.
What does it mean G-d's cubit, G-d's span (זרת) and how the universe is measured?