﴿4﴾ عَلَّمَهُ الْبَيَانَ
4. He taught him speech.
The blessed Verse in question makes a reference to one of the most significant Blessings second to the creation of man, saying: "God Almighty taught him speech." The Arabic word bayān ("speech") enjoys a wide range of meaning, applied to whatever clarifies something. Thus, it not only encompasses speech but also it connotes script, writing, and different intellectual and logical arguments clarifying complicated and sophisticated issues. The word encompasses all, though the core meaning is speech. 
Since men are habitually inclined toward speech, they underestimate it, but the fact is that speech is one of the most sophisticated and the most delicate of human acts. It may even be said that nothing is as sophisticated and delicate as speech, since sound production systems work together to produce different sounds. Lungs pump down the air and emit the same in time through larynx. Vocals tracts reverberate and produce totally different sounds to reflect satisfaction, wrath, requesting assistance, love, and hate. Then such sounds are produced with speed and particular delicacy through the tongue, lips, teeth, and the oral cavity. In other words, the monotonous and prolonged sound emitting from the larynx is fashioned in different forms and measures thereby different sounds are produced. On the other hand, the coinage of words is raised such that owing to intellectual developments, man coins different words to meet his material and spiritual requirements. It is a source of surprise
 According to a tradition narrated from Imam Sādiq (AS) regarding the exegesis of the blessed Verse "He taught him speech," he said: "Bayān is applied to the Greatest Divine Name (ism a‘zam) through which everything may be comprehended (Tafsīr Majma‘ al-Bayān, under the blessed Verse in question).
that there exists no limit as to the quantity of vocabulary and the number of languages spoken in the world is so large that it evades determination. Novel words and languages are formed in time. Some say that the languages of the world run to three thousand, but some even maintain that the number exceeds the same. They were seemingly after enumerating languages, since the number of regional dialects and accents far exceeds the aforesaid numbers as there are many instances in which the inhabitants of two adjacent villages speak two regionally different languages.
Another point is the rules of syntax governing clauses and also expression of arguments and feelings are carried out through intellect and reason as the soul of speech. Thus, speech is peculiar to man. It is true that many animals produce sounds to communicate but the sounds produced by them is so limited in number and they are rather vague compared to human speech which is of wide application and boundless, since God Almighty has provided man with the required faculty of speech. Furthermore, with due consideration of the role of speech in the developments of human life and the emergence and developments of civilizations, one may certainly believe that it is solely thanks to this great Blessing that mankind may pass down their knowledge and experience from one generation to the following one and thereby cause the advancement of knowledge and science and the developments in civilizations, religions, and ethics. Put the case that such great Blessing is withheld, human societies will rapidly move towards regression. If the word "speech" herein be applied to script and writing and even different kinds of arts, its extraordinary role in the life of mankind is furthered clarified. Now it becomes crystal clear why mention is made of God Almighty teaching man speech following the creation of man treated in the blessed Chapter in question which encompasses a compendium of Divine Blessings.
 Farīd Wajdī's Encyclopedia, vol. 8, p. 368, s.v. Lugha.