Great indeed, we confess, is the mystery of godliness:
He was manifested in the flesh,
vindicated by the Spirit,
seen by angels,
proclaimed among the nations,
believed on in the world,
taken up in glory.

—1 Timothy 3:16

It is a great mystery, if compared to all other mysteries

Creation was a great mystery, for all things to be made out of nothing, order out of confusion. For God to make man a glorious creature of the dust of the earth, it was a great matter. But what is this in comparison for God to be made man?

What are all mysteries, either of nature or hell, to this ‘great mystery’?

First of all, learn hence from blessed St Paul how to be affected when we speak and think of the glorious truth of God; that we should work upon our hearts, to have large thoughts and large expressions of it. St Paul thought it not sufficient to call it a mystery, but a great mystery.

—Richard Sibbes, 1577-1635