In ancient times, what would the Moon have looked like from the Earth?

It would have looked bigger. Active volcanoes might have been visible on it.

Explanation:

The most widely accepted theory of the Moon formation is Giant Impact hypothesis which states that a giant Mars sized celestial body: Theia hit planet Earth and the material that ejected out of the Earth coalesced and formed Moon. The Moon as observed today is moving away at a rate of around 4 cm per year which means that in ancient times it would have looked much bigger in the sky.

Frozen lava has been seen on the Lunar surface which are called as Maria (dark spots). In ancient times we could have witnessed those active volcanoes.

The moon would have appeared more vividly and brightly due to the absence of light pollution and smog