[And] taught him eloquence. (55:4)

Almuntakhab Fi Tafsir Alquran Alkarim

And He taught him the expression of his thoughts in words and intellectual acquaintance with, and perception of, fact and truth and good versus evil

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(55:4) and has taught him articulate speech. *3

[And] taught him eloquence. meaning

*3) One meaning of the word bayan, as used in the original, is the expressing of one'e own mind, i e. speaking and expressing one's thoughts and intentions. Its other meaning is to make distinction between things, which here signifies the distinction between good and evil, virtue and vice. According to those two meanings this brief sentence completes the above reasoning. Speech is the distinctive quality which distinguishes man from the animals and other earthly creatures, It is not merely the power of speech, but there are working behind It the faculties of reasoning and intellect, understanding and discernment, will and Judgement, and other mental powers without which man's power of speech could not operate at all. Therefore, speech is in fact an express symbol of man's being an intelligent being who has been endowed with freedom and authority, and when AIIah has blessed man with this distinctive quality, evidently the nature of instruction for him also cannot be the same a: would be suitable for the guidance of other creatures. LIkewise, another distinctive quality of vital Importance in man is that AIlah has placed in him moral sense by virtue of which he can naturally distinguish between good and evil, truth and falsehood, Justice and injustice, right and wrong, and this intuition and sense does not leave hlm even when he degrades himself to the lowest state of error and ignorance. The Inevitable demand of these two distinctive qualities is that the method of instruction for man's conscious and voluntary life should be different from the innate, natural mode of instruction under which the fish has been taught to swim, the bird to fly, and the eye in the human body itself to wink and see, the ear to hear and the stomach to digest, Man in this sphere of his life himself recognizes the means like the teacher, the book, the school, the verbal and written instruction and reasoning and discussion as the modes of instrutction, and does not regard the innate knowledge and intelligence as enough. Why should It then appear arrange that for fulfilling the responsibility that falls upon the Creator of educating man, He has made the Messenger and the Book the means of his education and instruction ? The mode of education has to suit the nature of the creation, And very rationally so; The "Qur'An" alone cart be the means of educating the creation that has been taught 'bayan"(speech) and not my other means that might salt the creatures which have not been taught the speech
 

[And] taught him eloquence. meaning in Urdu

اور اسے بولنا سکھایا