Why do we use the Lunar Calendar

[Arsalan]

OK apart from it being based on the evidences in Islam primary and secondary text.

Why do we measure time by the Moon?

[Al-Nasser]

because its easier to determine the start of the month by the moon shape.

and there is also one more thing...the lunar calendar is not weather linked....a beneift for example is...imagine that Hajj was set according to the georgian calnndar...June every year...that would have been hard for some people who can't stand hot weather but with the lunar calendar the Hajj season change from weather to weathe every few years