Turtur auritus (Heb. tor). The name is phonetic, evidently derived from the plaintive cooing of the bird. It is one of the smaller members of the group of birds which ornithologists usually call pigeons. The turtle-dove occurs first in Scripture in (Genesis 15:9) In the Levitical law a pair of turtle-doves or of young pigeons are constantly prescribed as a substitute for those who were too poor to provide a lamb or a kid. The offering of two young pigeons must have been one easily within the reach of the poorest. The admission of a pair of turtle-doves was perhaps a yet further concession to extreme poverty, for they were extremely numerous, and their young might easily be found and captured by those who did not possess pigeons, and you can find more about that here on st-takla.org on other commentaries and dictionary entries. In the valley of the Jordan, an allied species, the palm-dove (so named because it builds its nest in the palm tree), or Egyptian turtle-- Turtur aegyptiacus, Temm: is by no means uncommon. It is not improbable that the palm-dove may in some measure have supplied the sacrifice in the wilderness, for it is found in amazing numbers wherever the palm tree occurs, whether wild or cultivated. From its habit of pairing for life, and its fidelity to its mate, the turtle-dove was a symbol of purity and an appropriate offering. The regular migration of the turtle-dove and its return in the spring are alluded to in (Jeremiah 8:7) and Song 2:11,12 It is from its plaintive note doubtless that David in (Psalms 74:19) pouring forth his lament to God, compares himself to a turtle-dove.
Main reference: Smith's Bible Dictionary (1860s)
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