In the Islamic tradition,  during Ramadam,  there is a special night called the Night of Power, when angels are said to descend to earth, bringing peace. It is not known which night it is exactly, so the only attitude to have is one of waiting and watching. This is true for Advent also, but it even applies not just to special seasons but to the mystery in every moment:

God,
just like the Night of Power,
is hidden amidst the other nights
So that the soul
will go on seeking every night.

Oh young one,
not every night is the Night of Power
And yet,
not every night
is bereft of the Night of Power

Rumi

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