Isaiah (lx. 13) says: “The glory of Lebanon shall come unto thee; the fir-tree, the pine-tree, and the box together, to beautify the place of my sanctuary.” The “glory of Lebanon” is the
cedar-tree. These are not the evergreens mainly used in church decorations. At Christmas the holly is chiefly used, though those mentioned by Isaiah abound.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894