The moon's orbital motion of the Earth serves as a foundation for putting in context the motion of the faster moving Venus and Mercury around the Sun. The phases of the moon represent its orbital position to the central Earth using the light of the stationary Sun to provide the reference -

https://upload.wikimedia.org/wikiped...ikipedia.GI F

Move this principle to the satellites of other planets while it is difficult with normal telescopes to register the phases, the faster moving Venus moves around the parent Sun in much the same way as a satellite moves around a planet -

https://www.youtube.com/watch?v=zqZEgoJasPQ

The real challenge is accounting for the Earth's orbital motion in using this perspective but because the central Sun is the primary reference, it is safe to use the transition from left to right and from right to left depending on whether the planet is moving in front of the stationary Sun or behind it.