Short answer: in Jain scriptures, celestial descriptions are often symbolic or cosmological in a way that is not meant to be read as modern astrophysics. Different Digambar and Shwetambar traditions sometimes give different details, and the spiritual message is what Jainism emphasizes.

A few clear points you can keep in mind:

• Purpose of description: Jain cosmology uses celestial accounts to convey ideas about the universe, not to serve as scientific measurements. Size, distance, and motion are described in a way that supports spiritual symbolism (cycles, influences, bhav, etc.), not a test of modern astronomy.
• Versus science: Today we know the Sun is far larger than the Moon (the Sun’s diameter is about 400 times the Moon’s). Jain texts that speak of the Moon as “bigger than the Sun” are not providing a technical astronomy lesson; they reflect a particular traditional way of describing celestial bodies within a cosmological framework. The key is to read these lines in their proper context, not as a literal modern measurement.
• Different traditions: Digambar and Shwetambar commentaries may differ on exact phrasing or emphasis. It’s common for there to be multiple, sometimes poetic, descriptions in ancient texts. The spiritual meaning is more important than a one-to-one scientific equivalence.
• What to do in practice: If you want to understand a specific verse or description, look for:

- Its context in the sutra or purana (what topic is being discussed: cosmology, time cycles, or planetary motion?). - The commentary by a respected Digambar or Shwetambar scholar to see how they explain the line. - The underlying message (dharmic or ethical teaching) that Jainism intends to convey.

If you’re curious about a particular verse or text that says the Moon is bigger than the Sun, share the exact line or source and I can explain its Jain interpretation (including which tradition it belongs to and the spiritual meaning) in simple terms.