Psalms 78:43

How he set his signs in Egypt (R.V.): words borrowed from Exodus 10:1-2, "my signs which I have set among them." Cp. Psalms 105:27.

Only six, or, if Psalms 78:48 or Psalms 78:50 refers to the murrain, possibly seven, plagues are mentioned, the plagues of lice, boils, and darkness being omitted. The order is different from that of Exodus, coinciding with it only in the first and last plagues. It is of course possible that the Psalmist, treating the narrative with poetic freedom, only mentions the principal plagues, and intentionally omits the others: but it is noteworthy that the three which he does not mention are just those the accounts of which are judged by critics upon grounds of style to have been derived from different documents: the plague of darkness from the -Elohistic document," and the plagues of lice and boils from the -Priestly Code." The accounts of the remaining seven are in the main derived from the -Jehovistic document." See Driver's Introd. to the Lit. of the O.T., pp. 22ff. It certainly looks as if the Psalmist used the -Jehovistic document," while it was in circulation as a separate work.