What follows is a provisional translation (in other words, not official or authorized; see here for more) of a Tablet of ʻAbduʼl-Bahá, the original text of which is published in Yádnámiy-i-Miṣbáḥ-i-Munír, p. 390.
He is the All-Glorious
O son-in-law of Dhabíḥ, thou who expressest in the sweet tongue!* Languages are many and words are various, but the purpose of them all is to depict meanings and intelligibly convey the intentions of the mind. Hence, the meaning is the root, and that which the tongue uttereth is the branch. Strive as much as thou canst to study the essences of the divine significations and to unravel the celestial realities and mysteries, inasmuch as the living spirit of the world lieth in the meanings that exist in the human heart, and the force which animateth the body of creation consisteth in the truths present in the breath of God. One must be a conveyor of the heart and an elucidator of heavenly revelation. Such a one as this shall talk in every tongue and be a true speaker of all languages.
Glory rest on thee and on every firm and steadfast soul.
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* Originally lisán-i-malíḥ, probably a reference to the Persian language. See passages from Tablets of Bahá’u’lláh in Amr va Khalq, vol. 4, p. 278, lines 13–14, and Payám-i-Malakút, p. 111, lines 17–20, where Persian is described as malíḥ, and also Tabernacle of Unity, ¶ 2.55 (p. 51), where it is referred to by an equivalent word in Persian, shírín: “The Persian tongue is in truth exceedingly sweet [shírín] and pleasing.”
A typescript of the complete Persian text of this Tablet appears below. The punctuation has mostly been carried over from the source text, but I have added vowel marks in certain places to facilitate what I believe to be the correct reading of the text.