This is in the context of a treaty regarding a well in Beer Sheba, but it seems at first glance to have no relationship or bearing on the text. This typically means that I am lacking some sort of cultural or other significance.
So why is this seemingly random event noted in the text? What is the significance of this and what bearing or relationship does it have to the surrounding text? What purpose does it serve?
Interesting thing word "אשל"(eshel)(which here translated as tamarisk) is only used 3 times in the Bible two times in the 1 Samuel 22:6 and 31:13 where it means some type of tree (tamarisk) but Rashi doesn't like this version because it is not entirely understood why would Abraham all over sudden plant tamarisk tree so Rashi trying to find other solution! and the idea here they concentrate on the word planted rather on "eshel"!!!
Also good thing to note many different sages have different opinion what does this word mean!
אשל [AND ABRAHAM PLANTED AN] אשל(eshel') — Rab and Samuel differ as to
what this was. One said it was an orchard from which to supply fruit
for the guests at their meal. The other said it was an inn for lodging
in which were all kinds of fruit (Sotah 10a). And we can speak of
planting an inn for we find the expression planting used of tents, as
it is said, (Daniel 11:45) “And he shall plant the tents of his
(Bereshit Rabbah 54:6 "different names of the sages")
ויטע אשל, he planted some saplings there to serve as proof
that the well nearby was now his undisputed property. The word אשל(eshel')
describes certain plants (fruit-bearing) as In Samuel I 22:6 תחת האשל
ברמה, “under the eshel in Ramah). According to our sages in Beytzah 27
the reference is to tall trees which are difficult to uproot.
Our sages in Midrash Tehillim 106 understand the word אשל as an acronym
for אכילה, שתיה, לינה, “eating, drinking, staying overnight.” In other
words, Avraham established a hotel there to serve people passing that
region. He taught the people around Beer Sheva to practice the art
(virtue) of hosting strangers. In order to fulfill that virtue one
must provide the three ingredients represented by the three letters in
the word אשל. 33 ויקרא שם, Avraham used the opportunity of assembling
the local people and describing his and Sarah’s experiences to them in
order to give them first-hand evidence of how G’d had looked after him
against all odds.
He contrasted this with the local deities being worshipped who could not protect those who sacrificed to them. א-ל
עולם, he pointed out that his G’d was not only powerful locally, but
was a G’d Who was equally powerful allover the globe, seeing the globe
is His, He being the One Who had created it.
Ein Yaakov (Glick Edition), Sotah 1:29 (Gen. 21:33)
And Abraham planted a tamarisk-tree in Beer'sheba. Said Resh Lakish : "Infer from
this that he made an orchard and planted in it every kind of
delicacies." R. Juda and R. Nechemia both differ as to the explanation
of this passage. One says that the passage refers to an orchard and
the other says that it refers to an inn. It is evidently right
according to the one who explains it an orchard; for the passage says,
Vayita, (and he planted) but as to the one who explains it an inn,
what is the meaning of Vayita? (and he planted) ? Such an expression
we find in the following passage (Dan. 11:45) Vayita, he will pitch
the tents of his palace between seas and glorious holy mountains.
(Gen. 12:33) And called there on the name of the Lord.
Said Resh Lakish: "Do not read Vayikra and he called it, but Vayakri (Ib. b) and
he caused it to be called." Infer from this that Abraham caused every
traveler to call the name of the Holy One, praised be He ! How was
this done ? After they had eaten and drunk they would stand up to
bless Abraham, whereupon Abraham would say to them: "Have you then
eaten from mine? You have eaten from that which belongs to the God of
the Universe; therefore praise and bless Him who spoke and the world
came in existence."
Abraham planted the tree of hospitality. The Hebrew word, "eshel" is
an acrostic for ohel(food), sheina(lodging), and livuy(accompanying),
the three essential duties of a host.
The planting of the grove was independent of the treaty, but enabled by it.
Abraham was now in the land to which God had promised to lead him (Genesis 12:1), and the outcome of the second recorded meeting with Abimelech made Abraham confident and comfortable about finally setting down roots.
The appellation Yah-weh ’êl ‘ō-w-lām (the LORD God Everlasting), here in Genesis 21:33, is nowhere else found in the Bible. I'm pretty sure the planting of the grove was Abraham's attempt at leaving an everlasting legacy for his descendants, to commemorate the end of the journey that began in Ur and the beginning of life in the land of the promise.
The word אשל ’eshel, of Strong’s H0815 is always equivalent to ἄρουραν in Septuagint, Genesis 21:33;1 Samuel 22:6 and 31:13. > The sentence “στάχυσιν τῶν ἀλλοφύλων in Judge 15:5 is equivalent to “...ἀρούρας τῶν Παλαιστίνων...” in Flavius Josepho Antiquitates Judaicae 5.295, see also 6:14, and Apion 1:86 and 1:195. > Of Strong’s. In the book Exhaustive Concordance of the Bible, the word στάχυσιν means “grains in final development”, with the respective Hebrew word Strong's H7054 – qamah קָמָה Def: “standing grain”, time of harvest of the grains, to stand up, Wheat field. Gen 37:7; Exo 22:6; Det 16:9; Det 23:25; Jos 2:11; Jdg 15:5, 1Sa 4:15, 2 sa 14:7, 2Ki 19:26, Isa 17:5, Isa 37:27, Jer 51:29; Hos 8:7; Mic 7:6.
In the Targums of Onkelos, Gen 14:3, Gen 14:10 and Gen 21;33, the word פרדיסא means a garden, a paradise. A Glossary of Targum Onkelos. According to Alexander Sperber's Edition. Brill publishing house
In the Peshitta the word ܒܬܐ, root ܒܬ , means house, abode. A Compendious Syriac Dictionary. Payne Smith's.
** > Abraham planted a garden in Beersheba, to protect the well of water what was revealed by God for Hagar, that servants of Abimelech had seized. Gen 25:14; 25:19 and 25:25. There is a spiritual teaching in the sentence "I dug this well" in Gen 25:30.** >