This text comes from The Complete Poetical Works of John Greenleaf Whittier, a historical songbook transcribed on Wikisource and reproduced from the pinned revision linked below.
But what avail inadequate words to reach
The innermost of Truth? Who shall essay,
Blinded and weak, to point and lead the way,
Or solve the mystery in familiar speech?
Yet, if it be that something not thy own,
Some shadow of the Thought to which our schemes,
Creeds, cult, and ritual are at best but dreams,
Is even to thy unworthiness made known,
Thou mayst not hide what yet thou shouldst not dare
To utter lightly, lest on lips of thine
The real seem false, the beauty undivine.
So, weighing duty in the scale of prayer,
Give what seems given thee. It may prove a seed
Of goodness dropped in fallow-grounds of need.