And the Exalted said regarding this meaning:

“And do not recite your prayer [too] loudly nor [too] silently.” (Al-Isra 110)

Meaning: Do not proclaim it loudly to the disbelievers, and do not whisper it so quietly that it is hidden from the believers.

Why fasting was obligated by the Arabic month, not the Roman

And that He (the Exalted) mandated the fast according to the Arabic month [Lunar] and not the Roman month [Solar], so that the expert Knower might perceive the intent of that sign, which points toward the Luminous Month in which {Every day He is in a [new] state}.

Furthermore, He (the Exalted) mandated for us the abstinence from all food and drink to indicate that it is mandated for us to conceal the secrets of all Inward Gnosis, which is symbolized by these foods and drinks. For it is our duty to adopt the manners of the Worlds of Light and learn from their sciences, as He (the Exalted) commanded us by His saying: {O you who have believed, decreed upon you is fasting as it was decreed upon those before you} (Al-Baqarah 183).

That is, the Worlds of Light; for when they were in the human manifestation [Al-Thuhūr al-Basharī], they used to conceal the Inward from the disbelievers and present the Outward to them—this occurred after their [the disbelievers'] persistence in disbelief and denial of Divine Gnosis.