A very thorny question arises as to whether prophecies in the Old Testament are conditional or unconditional. Some of them appear to be one, and some appear to be the other. Problems arise whenever scholars seek to make one category that describes all prophecies. Hengstenberg, for instance, argues that all prophecies are unconditional. One wonders, then, how Hengstenberg deals with Jonah’s prophecy about Nineveh. Or, how does he deal with Jeremiah 18:7-10? I just finished reading Fairbairn’s chapter on this topic in his Interpretation of Prophecy. He has a taxonomy of prophecies that is well worth consideration. Fairbairn has three categories of prophecies. Of these, one is completely unconditional, one completely conditional, and one that has aspects of both. The first category he describes is one that has aspects of both. The prophecies of salvation that “disclose God’s purposes of grace to men” are unconditional with regard to their ultimate fulfillment. The only conditional elements have to do with “relations of place and time” (p. 63). The protoevangelion (Genesis 3:15) is an example of this type of prophecy. He writes, “[E]ven in this class of prophecies, as they do not proceed to their accomplishment in a lofty isolation from human interests and responsibilities, so the things belonging to them must be presented to men’s view as capable of being expedited or retarded by the line of behaviour they pursue; and while with God himself the end was seen from the beginning, and absolutely determined, yet particular issues might fitly enough appear to be suspended on the particular condition of the church or the world” (p. 64). The second class of prophecies he mentions has to do with “kingdoms that stood in a rival or antagonistic position to the kingdom of God.” These prophecies “were mainly intended to assure the hearts of God’s people, that whatever earthly resources and glory might for the time belong to those kingdoms, all was destined to pass away; that their dominion, however arrogant and powerful, should come to an end” (p. 68). These prophecies were about the foreign kingdoms, but they were usually directed towards God’s people. These prophecies do not, as a general rule, address moral issues (see p. 69). Many, if not most, of the oracles against the nations, fall into this category (for examples, see Ezekiel 25-32). The third class of prophecies is completely conditional. They are the prophecies about which Jeremiah 18:7-10 speaks. This class bears directly “upon men’s responsibilities” (p. 70). These are often directed towards the foreign nation. Jonah’s prophecy against Nineveh is a good example of this kind of prophecy. Jonah prophecies destruction, but Jonah obviously knows that this prophecy is conditional, because he did not want to give it to Nineveh, lest they repent, and then God would not bring upon them the destruction promised. Fairbairn comments on its seemingly unconditional form: “[T]he very absoluteness and precision of the form was the best adapted, it may be the only one actually fitted, to arouse slumbering consciences, and lead to serious repentance” (p. 73, emphasis original). This taxonomy helps us to avoid three particular problems with Old Testament prophecy. One is that of open theism. God doesn’t change his mind. With the prophecies that have conditional elements, God immutably carries out His complex purposes, such that if the people change (of which outcome God already and immutably knows), then the outcome changes, humanly speaking. Secondly, this helps us to make sense of prophecies like that of Jonah that seemingly do not come to pass. As we know, one of the criteria for true prophets is that their prophecies must come to pass. Of course, liberals tend to use a very literalistic heremeneutic in order to “prove” that Old Testament prophecies are not fulfilled. This is another subject that Fairbairn addresses in this same chapter, incidentally. Thirdly, it also helps us to avoid the problems associated with extreme positions, like that of Hengstenberg, on the one hand, who argues that no prophecies are conditional; and other opposite positions, that argue that all prophecies are conditional. The problem with the latter position is that the criteria for prophecies coming true would be meaningless if the prophecies were always conditional. The prophet whose prophecy doesn’t come to pass could then conceivably always use the excuse, “Well, it was conditional.” I commend Fairbairn’s careful taxonomy. There might be tweaks that would be necessary to his categories (although I can’t think of any right off). But this is a helpful way of making sense of enormous swaths of Old Testament prophecy.