Both psalms are pre-Exilic, and probably formed part of the temple liturgy. (D. A. Robertson, Linguistic Evidence in Dating Early Hebrew Poetry [Missoula, Montana: SBL, 1972], pp. 135, 138, 143, 15–52; A. Hurvitz, The Transition Period in Biblical Hebrew: A study in Post-Exilic Hebrew and Its Implications for the Dating of Psalms [Jerusalem: Mossad Bialik, 1972] finds no linguistic reason to consider these psalms late.) A comparison of the three different presentations indicates a certain plasticity in the Israelite tradition of the plagues. The coexistence of conflicting, somewhat contradictory, parallel plague traditions tells against any attempt to explain the order of the ten plagues as reflecting a connected series of natural catastrophes and provides a qualification to the discussion above concerning the possibility of a sequential disaster. Although it is not impossible that some natural disasters ultimately lie behind the various plagues, the traditions in their extant forms cannot be employed to reconstruct what actually occurred. The implication of the three lists of plagues is that Israel did not preserve the details of the plagues or their number for their own sake, but rather recalled the significance of the plagues as events demonstrating a theological principle.