There is more than one type of typology in Scripture, but we can break typology into two neat classes. First, there is typology that is more prophetic; second, there is typology that is more typological. The first is typology that is already focused on the future. The second is typology that shows little focus on the future, but nevertheless is used by a later writer as though the earlier text was about the future. In this discussion, I will only address the first type, that is, typology of the prophetic type.
Let’s look at an example. Isaiah 7:14 records, “Therefore the Lord himself will give you a sign. Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel.” Although this text is vigorous debated, it is clear that all this coming child was to be and accomplish in Isa. 7 – 9 is not fulfilled by Isaiah’s son. In the original context of Isa. 7, God is giving Isaiah and his wife a son who acts as a sign. The original Hebrew of the term, “virgin,” is ‘alma, and it means “young maiden” but not necessarily a virgin. The Septuagint, the Greek of the OT, renders ‘alma as parthenos, which is accurately translated as “virgin” or “unmarried person,” likely implying a youthful person before they become sexually active. The term, ‘alma, which Isaiah and Israel would have used in their conversation is unclear enough that Isaiah’s wife could still be identified as a “young maiden” even if she was already pregnant. The translators of the Septuagint were also excellent interpreters because they recognized, presumably, what I am noting as well: the son of Isaiah did not fulfill all that God assigned to this “Immanuel” (“God with us”). So where is the typology you might ask? Isaiah’s wife and son are together a type of the virgin Mary and Jesus; said differently, Jesus and Mary are prefigured in Isaiah’s wife and son. Isaiah’s wife was a young maiden and Mary is a young maiden. But Mary fulfills Isa. 7:!4 in more ways (she is an actual virgin) than what Isaiah’s wife does. Similarly, Isaiah’s son was a sign but did not fulfill all the notable accomplishments this “Immanuel” was prophesied to do; Jesus does fulfill this “Immanuel” prophecy with the included accomplishments in Isa. 7 – 9 to an exceptional degree. Thus, although we have typology (Isaiah’s wife and son), it is also a prophecy because it is already focused on the future in the details of what is prophesied of this “Immanuel.” This is typology of the prophetic type because there is clearly a type but also a manifest future orientation. Isaiah 7:14 is only marginally fulfilled in Isaiah’s wife and his son, which we can call the “near and partial fulfillment” of Isaiah 7:14. Jesus and Mary are the “full fulfillment” of this typological prophecy because they perfectly represent the original type’s significance and because the “fill up” or “satisfy” the prophecy of Isa. 7:14.