'Referring to the Tablet of Baha'u'llah which was revealed in Sulaymaniyyih and which began "Create in me a pure heart, O my God,...", Abdu'l-Baha said: "When, for the first time, I read this Tablet, I wept openly." (Words of Abdu'l-Baha, as recalled by Dr. Diya Baghdadi, unpublished memoir)'
Stories of Baha'u'llah, Compiled by Hand of the Cause of God Ali-Akbar Furutan, p. 20
In 1990 the elderly and ailing Hand of the Cause of God William Sears, (he died less than a year and a half later), addressed a rapt audience composed mostly of Baha'is. It was in an auditorium as part of the Desert Rose Baha'i Conference in Tucson, Arizona. From the podium on the stage he held up his open prayer book for all to see. The following is my recollection of the gist of his accompanying words, which were fraught with emotion:
I don't know if you can all see this from where you're sitting, but I have on this page of my prayer book a small red heart, like a sticker that children use, up in the corner, to help me find this prayer. It's the one that begins 'Create in me a pure heart, O my God...'. I read this prayer once, twice, sometimes many times a day. I don't have that pure heart yet, but someday I'm going to get it.
And then he read aloud the prayer.
"Create in me a pure heart, O my God, and renew a tranquil conscience within me, O my Hope! Through the spirit of power confirm Thou me in Thy Cause, O my Best-Beloved, and by the light of Thy glory reveal unto me Thy path, O Thou the Goal of my desire! Through the power of Thy transcendent might lift me up unto the heaven of Thy holiness, O Source of my being, and by the breezes of Thine eternity gladden me, O Thou Who art my God! Let Thine everlasting melodies breathe tranquillity on me, O my Companion, and let the riches of Thine ancient countenance deliver me from all except Thee, O my Master, and let the tidings of the revelation of Thine incorruptible Essence bring me joy, O Thou Who art the most manifest of the manifest and the most hidden of the hidden!"
(Baha'u'llah, Prayers and Meditations by Baha'u'llah, p. 248)
This prayer can be found in many compilations of Baha'i prayers.