The logic of Brevard Childs' canonical approach flows out of a commitment to understanding the reality testified to by the historical prophets and apostles. He does not start with an a priori commitment to the final form of the text, synchronic exegesis for the sake of it, or a broad thematic approach to Scripture. Rather, he looks to the historical tradents that gave us what was to become Scripture and attempts to understand what they were getting at. From that diachronic analysis his gaze is directed elsewhere, but only after the tradents themselves have redirected him.
An illustration of Childs' understanding of the nature of these tradents can be found in his source critical analysis of the Book of Exodus. Childs finds here a diversity of tradents who were involved in the production of the text. The “Plagues of Egypt” narrative (Ex 7:8-11:10), for example, consists of Priestly and Jahwist sources with small fragments of the Elohist (P, J, E), supplemented by late glosses.1 Each source has its own narrative account of the plague, drawing on a common body of pre-existent oral tradition, and each witness originally stood independent of the others. These authors responded to their authoritative tradition in different ways, yet guided by the common desire to shape that tradition for the next generation of faith.
The Jahwist, for example, “shows tremendous freedom and imagination in fashioning his account,” despite the “traditional forces bearing on the writer which had determined in general the conclusion and general structure of the narrative.”2 J builds in a concession motif, for example, creating a sense of increased tension in which Pharaoh's reneging on a previously granted concession (8:28; 9:28) turns to an impasse created by the inadequacy of Pharoah's later offer, (10:8-11), climaxing in the final breakdown in communication (10:24-29). In addition to this, the Jahwist skilfully portrays Moses and Pharaoh as competing antagonists—despite the roles which tradition had assigned to them—and creates an interesting tension between the LORD's absolute demands for release and his willingness to negotiate.3
The Elohist, on the other hand, is only preserved in fragmentary form, though as a continuous strand nonetheless. The movement of his narrative follows that of the Priestly writer and seems to reflect more the original tradition which was their common source. The plagues come in quick series and have no affect on Pharaoh because of the hardness of his heart.
The editorial integration of E with J results in an expansion of J's basic schema, such as the transition from the Lord's executing the plague in J to Moses' being the agent.
Again, the Priestly source reflects a variant tradition to that of J. For example, there was a distinction between plagues and miracles which originally served to distinguish the traditions of P and J. In P's schema Moses and the magicians compete in the performing of miraculous signs, yet the signs soon take on the characteristic of plagues, whereas the J source speaks initially of plagues, but these shortly function as signs. P also interprets the function of the hardening of Pharaoh differently to E: rather than plagues being a result of Pharaoh's hardness, Pharaoh is hardened so that the Lord can multiply his signs. Another difference to J and E is that for P the killing of the first-born does not belong the the plague tradition but to an originally independent Passover tradition. This plague is neither a plague in a sequence nor a sign, rather in P's account it functions to bring about the release of the Israelites, in fulfilment of the promise of 7:3-5. P also links the plague tradition to the crossing of the sea, in contrast to J, for whom the sea tradition belongs to the tradition of the wanderings in the wilderness.
Not only do these authors actualize their sacred traditions in differing ways, the combination creates an actualization of its own. Both the passover and reed sea traditions are brought into closer proximity to the plague tradition and there is a merging of miracles and plagues so that signs function as plagues and plagues serve as signs. In addition to all this, the various glosses evidence further theological reflection on the content of the tradition, actualizing the text for later generations in various ways. In 9:14-16, God's long-suffering does not represent self-restraint rather than impotence. 9:19-21 evidences a didactic interest to distinguish between “god-fearers” and the unbelievers, providing a testimony that the solidarity of judgement against all Egypt could always be relieved by faith in God's word. 10:1b-2 is a theological expansion, Deuteronomic in character:
The author uses the hardening vocabulary of J, but the theology of P. Any clear-cut distinction between sign and plague has also been lost. The expansion reflects the early interest in the actualization of the plague for a later generation. Here the Deuteronomic interest is more didactic than liturgical (cf. Ex.13.14f.; Josh.4.21). The understanding of the plagues as a testimony to God's great power by which to make sport of mighty Pharaoh is at work.4
In terms of Childs' canonical approach, the following key ideas ought to be borne in mind: 1) there is a dialectical relation between later witness (the sources and their redactors) and prior tradition. Prior witness constrains later interpretation, later interpretation shapes prior tradition. The prior tradition is thus religiously authoritative; 2) this process of interpretation was theological and aimed at identifying God's will for later generations of faith (contra many proposals from contemporary scholars today, who consider the primary force at work in Israel's tradition as political manipulation); 3) the redactional shaping of the sources is an extension of the source's own activity of shaping the tradition. There is thus continuity: the continuity of (dialectical) theological reflection, indeed reflection on the content of the tradition. One could no doubt claim that the tradition prior to these sources also partook of this same process. 4) The final form represents the culmination of a process of theological interpretation within the context of a broader understanding of the will and identity of God.
1Cf. Exodus, 131, for Childs' suggested source divisions with glosses.
2Childs, Exodus, 135.