Baha'u'llah's praise for Mirza Yahya's "verses"

During his ministry as head of the Babi movement, Mirza Yahya wrote a book called the Kitab-i Nur. Baha'u'llah wrote a letter in the Baghdad period urging Babis to copy it, describing it as verses from God:

Provisional translation:

"The Kitab-i Nur was not sent despite repeated insistence. Do not neglect it. It is very necessary for all the people of the Bayan. Janab-i Mulla Zayn al-Abidin, the blessings of God be upon him, must make a great effort to complete (copying) it. By the Lord of the heavens and earth! Verily, it is a noble and beloved book and the verses [ayat] of the Help in Peril, the Self-Subsisting. Copy it in the best of handwriting as perfectly as you can. Then read it with love if you desire to ascend to the heavens of attraction and rise to the lofty clouds of sanctity."

You can find the passage in the full text of Baha'u'llah's letter on the official Baha'i website (it's the last paragraph).