there is no other Son, for he is only-begotten. Hence the one and only Father is the Father of the one and only Son, and only in the case of the divinity have the names “Father” and “Son” always been stable and always are. 1.16.3. But among human beings, if someone is called a father, he is nonetheless another man’s son; and if someone is called a son, he is nonetheless another man’s father. Hence among human beings the names ‘”father” and “son” are not preserved in their proper senses. 1.16.4.
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