an act by which any one takes another into his family, owns him for his son, and appoints him for his heir.—The custom of adoption was very common among the ancient Romans; yet it was not practised, but for certain causes expressed in the laws, and with certain formalities usual in such cases: they first learnt it from the Greeks, among whom it was called ταξινομία. This adoption was a sort of imitation of nature, intended for the comfort of those who had no children: wherefore he that was to adopt was to have no children of his own, and to be past the age of getting any; nor were eunuchs allowed to adopt, as being under an actual impotency of begetting children; neither was it lawful for a young man to adopt an elder, because that would have been contrary to the order of nature; nay, it was even required that the person who adopted should be eighteen years older than his adopted son, that there might at least appear a probability of his being the natural father.—Among the Turks, the ceremony of adoption is performed by obliging the person adopted to pass thro' the flint of the adopter. Hence, among that people, to adopt, is expressed by the phrase, to draw another through my shirt.
It is said, that something like this has also been observed among the Hebrews; where the prophet Elijah adopted Elisha for his son and successor, and communi- cated to him the gift of prophecy, by letting fall his cloak or mantle on him. But adoption, properly so called, does not appear to have been practised among the ancient Jews: Moses says nothing of it in his laws; and Jacob's adoption of his two grandsons, Ephraim and Manasseh, is not so properly an adoption, as a kind of substitution, whereby those two sons of Joseph were allotted an equal portion in Israel with his own sons.
Adoption is also used, in theology, for a federal act of God's free grace; whereby those who are regenerated by faith, are admitted into his household, and entitled to a share in the inheritance of the kingdom of heaven.