This just struck me so I am putting it here for safe keeping.
I have, in other writing, commented on the bracha of "atah kadosh" in the shmoneh esrei -- how in one way of reading, calls all humans who daven "kedoshim" and this puts on on the same level as angels, and also, equates us, in this sense, with God and his holiness. But I just found another, similar idea.
In the Shabbat morning davening, we say "yismach moshe" (and Moshe will be happy). I looked up online to try and figure out what this is referring to. Why is it in the future tense and not the past -- the paragraph seems to be talking about events in the desert! I found a page which pointed out that future happiness is mashiach-era based. Moshe will be happy because he gets a portion in the messianic age and he earned it by being an eved ne'eman, a loyal servant to God. That seems like a tough level to reach. I can't be as great as Moses so I won't have the option to have that happiness. Unfair, I say.
But we fix that by adding musaf to our Shabbat prayer routine. In musaf, we say "yismechu b'malechutcha shomrei shabbat" (those who guard the sabbath will be happy in your kingship) - we will earn a place in the era when God is king over all simply by guarding the Sabbath! Maybe by placing that line in the musaf prayer, the extra prayer recited on the Sabbath and holidays, we are earning that place by praying (in some weird, recursive logic loop). The Sabbath was sanctified as special so that we could, through our adherence to Sabbath laws, earn something beyond this world.
Maybe we can't be as dedicated and loyal servants as Moses was but God gives us an avenue we CAN achieve in order to earn that divine happiness, guarding the Sabbath.