Baha'u'llah acknowledges that Isaiah wrote of Him:
This is an Announcement whereat the hearts of the Prophets and Messengers have rejoiced. This is the One Whom the heart of the world remembereth, and is promised in the Books of God, the Mighty, the All-Wise.. I am the One Whom the tongue of Isaiah hath extolled, the One with Whose name both the Torah and the Evangel were adorned. (pdc 34) (15:47)

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