Gospel harmonies have a long history, dating back to the second century, and come in two main varieties:
1. Parallel
Accounts of similar events in different gospels appear in parallel columns so that readers can compare all four accounts side-by-side. This approach allows the distinctive voice of each author to remain, while visually emphasizing continuities and discontinuities–a story found in all four gospels looks much different on the page from a story found in only one. Typically parallels appear at the pericope or story level rather than at the word or verse level. Nearly all gospel harmonies we see today fall into this category.
2. Blended
A blended, or composite, gospel attempts to present the four disparate accounts as a single story, often picking a dominant gospel and using other gospels to fill in gaps. This approach emphasizes the unity of the gospel story while often smoothing over differences small (word choice) and large (chronology of events) among the gospels. It also diminishes the literary structure, purpose, and language of the individual gospel writers. In exchange for these drawbacks, a blended gospel (ideally) gains simplicity and narrative clarity.
The earliest known gospel harmony, the Diatessaron, dates from around 160 and is a blended account. Since the Protestant Reformation, however, parallel column-style harmonies have dominated.
A Digital-First Harmony
A blended digital gospel harmony can overcome many of the shortcomings of a static, print-based blended harmony for two reasons: unlimited space and interactivity.
Unlimited space allows harmonizers to make visible the choices they’re making as they blend accounts. Rather than choosing a single word and omitting variations from other gospels, they can show all the variations and allow the reader to check their work. This approach imports one of the advantages of parallel harmonies: it’s easy to see the similarities and differences among the different gospels. I feel that presenting these variants inline rather than visibly separate–as in different columns–only minimally disrupts the reading flow while giving readers the ability to understand the complexities involved for themselves.
Interactivity addresses three major problems of a blended gospel: which account takes priority, how to arrange the material chronologically, and determining whether different gospels are recounting either the same event with apparent discrepancies or two different events (e.g., Matthew’s sermon on the mount and Luke’s sermon on the plain). The solution in each case: let the reader choose.
In this way, harmonizers are creating less a product and more a system that allows readers to explore the system and draw their own conclusions.
Any blended harmony necessarily dilutes the intent of the original author–adding or omitting details is part of the editing process. However, by making such changes explicit and explorable, an interactive blended harmony can minimize the dilution.
Example: Blended Palm Sunday
This blended Palm Sunday account illustrates some of what I discuss above. All variations appear near the related main text. (The extent of your browser’s support of the <ruby> element dictates where the variations appear.) I also added some minimal interactivity: selecting the checkboxes changes the text from the selected gospels to red–in this case, all the text from Matthew is red. You can imagine other interactivity: maybe you can excise certain gospels, or choose which ones receive priority. John, for example, presents the Palm Sunday story in nearly reverse chronological order compared to the other three gospels; rearranging the synoptic narrative to fit John’s account would be an interesting exercise.
This example is just a proof of concept and took a surprisingly long time to put together. I can only imagine that constructing a complete blended harmony of the gospels at this level of detail would involve a large investment of time with no realistic commercial return. Kermit Zarley in 1987 published The Gospels Interwoven, an NIV blended gospel blurbed by Billy Graham; it was out of print a decade later and survives only in print-on-demand form. If a product like that doesn’t find commercial success, the one I’m proposing would find even less. Still, I like to think that this proposal serves as an example of a digital-first product that wouldn’t be possible in print form; it’s a bit ironic that technology could reintroduce and potentially improve the oldest approach to harmonizing the gospels: blended gospels like the Diatessaron.