Deep Calleth unto Deep

Deep are thy waters, Love, in every heart.
Who is there that hath ever sounded these?
Lightly we sail the still, unfathomed seas.
Without a compass and without a chart.
Yet are there two that have essayed this art —
The mother with her firstborn on her knees.
The son whose cordial spirits shrink and freeze
To see the life from whence he lived, depart.
These who have learnt that all their strength is weak.
These who have striven in vain and vainly found
Their resolution but an idle freak
And all their spoken faith an empty sound.
These have let down the plummet; could they speak,
They would but say, "It never touched the ground."