Genesis 21:33: Abraham's Tamarisk

In preparation for a workshop with the translators on Genesis, I came upon this article for the most recent edition of the Journal for the Evangelical Study of the Old Testament, written by Matthew Umbarger of Newman University.

His article discusses the meaning of Genesis 21:33 which reads,

Abraham planted a tamarisk tree in Beersheba, and called there on the name of the LORD, the Everlasting God. 

His conclusion, after surveying the various interpretations of this text, including rabbinic and evangelical literature, as well as parallels in Akkadian texts:

Like a Mesopotamian king, Abraham plants a tamarisk in what is essentially his courtyard. Perhaps the tamarisk-planting underlines the preceding episode in which Abraham asserts himself as an equal to Abimelech. But the real significance of the tamarisk is its religious connotations. Since the planting of the tamarisk immediately follows the interaction with the Philistines in the text, it is possible that here the purifying properties of tamarisk are hinted at, with Abraham immediately planting the tree to cleanse the sacred environs of his well after its recent profanation on the part of the Philistines. In any case, Abraham, nomad that he is, does not build a temple, but his tamarisk, with its purifying, sanctifying properties, helps him to craft a simple but functional place of worship where he can call on the name of the Lord. According to the Genesis account, Abraham is a Mesopotamian chieftain and follows Mesopotamian customs in his planting of the tamarisk, and by so doing creates a shady place to enjoy sacrificial banquets zoned off from threats to ritual purity. 

(HT: Exegetix)