We understand the moon does not self-produce light. The Bible's description of the moon as a light is a matter of semantics.
Why does the Bible call the moon a light?
The first place in the Bible to describe the moon is Genesis 1:16: "And God made the two great lights—the greater light to rule the day and the lesser light to rule the night—and the stars." Other places in the Bible that describe the moon as light include Isaiah 30:26, Isaiah 60:19, Ezekiel 32:7, and Mark 13:24.
The moon does allow the night to be lit, though it does not produce the light itself. Calling the moon a light is similar to talking about sunrise. The sun doesn't physically rise in the east, but the earth's rotation makes it appear to rise. This is called phenomenological language, and we use it regularly.
It clearly says in the Genesis account that the two lights were created together, but not precisely saying they each produce light, only that they provide light. Genesis 1 is not attempting to call the moon something other than what it is.
Do not be distracted by the description of the moon as light. The moon provides the light, yes, from the sun, but it is still necessary to light the night. It's like saying the light bulb provides light in the lamp, but arguing it is the electricity which provides the actual power. God does not give us all the precise scientific details of His creation. Rather, He communicates in ways we can understand and appreciate.
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