What most critics appear to agree on when examining these principles is the fact that there must be some sort of literary interdependence among the Synoptic Gospels.

The verbal agreement among the Gospels is one very strong indicator of such interdependence. Wallace regards both the independence theory and the Spirit Inspired hypothesis, generally held by laypeople, as naive from a scholarly viewpoint. Had the three Gospels simply been eye witness accounts of the same event, for example, there could not have been such very specific and frequent verbal agreements among them. Furthermore, the sequence and interpretation of events would likely have differed far more significantly.

The inspiration of the Holy Spirit, on the other hand, is regarded as naive for its lack of critical focus; providing a reasons for the similarities among the texts, but not for the differences. For Wallace, the most persuasive argument for literary interdependence is offered by the identical nature of parenthetical material such as "let the reader understand" in Matthew 24: 15 and Mark 13:14. The identical nature of these and other verbal utterances suggests that the authors must have seen each other's work at some point. The question remains what the precise relationship is among these Gospels.

It is perhaps easiest to briefly review the hypotheses that have been disproved or at least proved unlikely in the light of research done and the knowledge accumulated now. First, eye-witness accouns seem highly unlikely, since there could not have been such verbal agreement without some sense of text as well. Being inspired by the Spirit is also fallacious, since, it suggests that the texts should have only similarities, being flawlessly inspired, with no or very little difference.

The most convincing arguments, for me, have been the priority of Mark in terms of chronology, as well as the interpretation that there must have been some original text the authors used for their work. These would explain both the similarities and differences in the texts, as seen above.

According to Sanchez,

a significant point against the idea of the "Q" gospel or "Ur-Gospel" is the fact that no such text has been discovered. While the proponents of this idea hold that it is indeed no longer in existence, it does appear quite possible that there might have been such a common text from which to work. In this light, it could be more likely that the authors worked from surviving fragments, which would explain not only the similarities, but also the differences as the authors worked to fill the gaps in their knowledge.

In my view, the final theory seems to be most likely. It is more unlikely for fragments of information to vanish in the mists of time than for an entire and important script to do so, especially if this contains the direct words and actions of Christ. Also, the unlikely nature of

These hypotheses are the ones that make the most compelling arguments from a critical point-of-view.
In conclusion, it appears most likely that the Synoptic Gospel writers did so with the benefit of at least parts of surviving text. This seems to be the most likely explanation for the similarities in the texts. On the other hand, the differences appear to be explained by the same thing. Being human, each Gospel writer would have embellished or added some information to fill the story and provide logical pathways among the episodes.