Early Latin Pro-Nicenes had described the relationship between the Father and the Son by using an analogy with human fatherhood. Just as human fathers give birth to sons who share the father’s nature, they argued, so too does the divine Father give birth to a Son who shares the divine nature. But using this analogy could lead to subordinating the Son to the Father, as human sons are subordinate to their fathers. The article shows that Augustine solves this problem by arguing that the names “Father” and “Son” indicate relationship but not substance.