We see the use of this terminology all over the New Testament. For example, Jesus says, “Today this Scripture has been fulfilled in your hearing” (Luke 4:21). Elsewhere John says that the events of the crucifixion happened “that Scripture might be fulfilled” (John 19:36). These are just two of the numerous examples in the New Testament. The question is, what does it mean?
The most common understanding of the “fulfilled” language is that of prediction-actualization. The Old Testament prophets predicted certain things, and the actualization of that prophecy comes to pass (i.e., it was fulfilled). For example, in Isaiah 7:14 we see a prophecy concerning a virgin giving birth. In Matthew 1:22–23 we see that this prophecy is actually realized (fulfilled) in the virgin birth of the Messiah, Jesus. Although this is a valid understanding of “fulfilled” language, it is important to understand that it is not sufficient to explain all uses of the Scripture being fulfilled.
There are multiple examples where Old Testament passages are said to be fulfilled in the New Testament, even though the Old Testament passages are NOT predictions. One instructive example is James 2:21–23. There James points out that when Abraham offered up Isaac on the altar (Gen 22), it was a fulfillment of Genesis 15:6, “Abraham believed God, and it was counted to him as righteousness.” It is clear that Genesis 15:6 is not a prophecy concerning Genesis 22. However, James has no problem saying Scripture was fulfilled. Why?
James is making the case that Abraham’s works demonstrated the genuineness of his faith. Thus, in line with this argument, James is stating that Genesis 22 is the outworking or natural conclusion of the faith Abraham demonstrated in Genesis 15:6. In other words, fulfillment formulas in Scripture are not always prediction-actualization. They are often a reference to the working out of Old Testament theology in some way.
Another similar example which should solidify this point is Acts 1:15–20 and the replacement of Judas. In verse 16 Peter notes that Scripture “had to be fulfilled.” He then goes on to quote the two psalms in verse 20 (Psalm 69:25 and 109:8). Both of these psalms refer to David’s historical circumstances, and are not predictions. However, Peter specifically applies these passages to the present circumstance of replacing Judas. Importantly, Peter changes the Old Testament text from “let their camp be desolate” to “let his camp be desolate.” This signifies that Peter is viewing this as a specific application to Judas.
Both Psalm 69 and 109 deal with the opposition and betrayal of the Davidic king. Because the disciples were familiar with these psalms, they were also equipped theologically with how to think through their own situation of opposition and betrayal by Judas. Thus, Scripture “had to be fulfilled” in the outworking of how to deal with those who opposed and betrayed the Davidic king. Thus, Psalm 69 and 109 can be referring to David’s situation, and at the same time provide the paradigm through which the disciples interpret their own situation, giving justification to the use of “fulfillment” language as the working out of ramifications of the Old Testament texts.
In sum, although prediction is a part of Scripture being fulfilled, it is only a part, and not the complete picture. Fulfillment is a broader concept which includes prediction, as well as the natural outworking of Old Testament theological concepts.