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.
“The cross, if rightly borne, shall be
No burden, but support to thee;”
So, moved of old time for our sake,
The holy monk of Kempen spake.
Thou brave and true one! upon whom
Was laid the cross of martyrdom,
How didst thou, in thy generous youth,
Bear witness to this blessed truth!
Thy cross of suffering and of shame
A staff within thy hands became,
In paths where faith alone could see
The Master’s steps supporting thee.
Thine was the seed-time; God alone
Beholds the end of what is sown;
Beyond our vision, weak and dim,
The harvest-time is hid with Him.
Yet, unforgotten where it lies,
That seed of generous sacrifice,
Though seeming on the desert cast,
Shall rise with bloom and fruit at last.