Slightly backtracking, show deference to biblical couple going steady (2,2,4,4)

I believe the answer is:

on an even keel

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'steady' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for on an even keel that I've seen before include "Running smoothly" , "Steady" , "Well-balanced" , "In a stable condition" , "(Going) calmly" .)

I've seen this clue in The Guardian.

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