Genesis 25:27

"Dweller of tents" refer to the tent of Shem and Aver

And the lads grew; and Esau was a man of idleness to catch birds and beasts, a man going forth into the field to kill lives, as Nimrod had killed, and Hanok his son. But Jakob was a man peaceful in his words, a minister of the instruction-house of Eber, seeking instruction before the Lord.

"Knew the hunt." [Esau] was always full of deception, for most wild animals catch [their prey] using deception. But Jacob was the opposite of Esau because he was a "plain man." Esau was also a "man of the field." And Jacob "stayed in the tents." And it seems likely that its meaning is like "those who dwell in tents and amidst herds." (Gen. 4:20)

יודע ציד, hunting venison and retrieving the animal to serve as food.

יושב אהלים, tending his father’s flocks as we explained already in connection with 4,20 יושב אהל ומקנה.

איש שדה, an expert farmer.

יושב אהלים, the plural mode indicates that the Torah speaks of two distinctly different kinds of tents; one is the tent used by shepherds, the other the tent described as בל-יצען described in Isaiah 33,20, (a reference to Jerusalem or the Temple). The function of that “tent” is to help people come closer to G’d and to gain insight into His ways and as a result to become holy, inspired by His glory.

ויגדלו הנערים, as soon as they grew up their activities diverged completely from one another, one concentrating on mundane activities, activities which showed immediate profitable results, the other concentrating on the acquisition of knowledge, wisdom, i.e. abstract matters. One was an extrovert, at home in the fields, mountains, etc, whereas the other was an introvert as reflected in the term יושב אהלים.

אהלים, the reason why the Torah wrote this word in the plural mode is because Yaakov studied with any wise man he came across. He was indiscriminating in this regard, being totally devoid of deceit or evil, wanting only to amass knowledge.

ויגדלו הנערים, “the lads grew up;” according to Rashi and the Midrash, as long as the twins had not attained the age of 13 one could not tell their characters apart. As soon as they reached that age it became evident that they pursued totally different objectives in life. The matter can be compared to thorn bushes growing up next to myrtles. Until they have developed, they look alike and neither emits any fragrance. After a while, the fragrance emitted from the myrtle distinguishes it drastically from the thorns of the thorn bushes. You might question that according to Rashi, Esau was only thirteen years old when he already chose to worship idols, while the same Rashi claims that when Esau sold his birthright he was `15 years old on the day of Avraham’s burial, and he claims that Avraham died five years earlier than originally decreed by G–d to spare him watching his grandson become an idolater; how can these two statements be reconciled, if Esau became an idolater already at the age of thirteen? This question has actually been raised in the Jerusalem Talmud! The answer given there is that Esau hid his idolatry for two years so that during the last two years of his life, Avraham had not become aware and grieved by it. As soon as Avraham died, Esau no longer hid the fact that he had become a heretic.