What is "by cock and pie"

Pie \Pie\, n. [F. pie, L. pica; cf. picus woodpecker, pingere to paint; the bird being perhaps named from its colors. Cf. Pi, Paint, Speight.]

1. (Zo["o]l.)

   1. A magpie.

   2. Any other species of the genus Pica, and of several allied genera. [Written also pye.]

2. (R. C. Ch.) The service book.

3. (Pritn.) Type confusedly mixed. See Pi.

   By cock and pie, an adjuration equivalent to ``by God and the service book.''
   --Shak.

   Tree pie (Zo["o]l.), any Asiatic bird of the genus Dendrocitta, allied to the magpie.

   Wood pie. (Zo["o]l.) See French pie, under French.