It is very curious to notice how the first sanctuaries seem to have been woods, forests, and groves. And it is equally remarkable to notice how, after they were used for true and spiritual worship, they came to be employed exclusively for idolatry — so much so, that in the rest of this blessed Book you will hear God often commanding them utterly to pull down the groves, because those groves had been made places where idols were worshipped. The brass serpent was made by God's command, its healing virtue was given by God Himself, and the people were divinely told to look at it. But after it had served its purpose, the same people tried to make a god of it. In this instance men took that which was true and good originally, and made such a bad use of it that God commanded it to be ground to powder as "a thing of vanity and as nothing." These grove sanctuaries came to be desecrated, and therefore He commanded them all to be pulled down. One can see in these groves the first idea of a cathedral. Let any one stand in a lofty avenue of oaks, with their branches intertwining and interlacing, and he will see the nave of a Gothic cathedral. The tracery on the roof, the groined arches, the columns, and the pillars with their picturesque capitals, all is but man trying to embody in the stone what nature has so magnificently developed in her forests, and to perpetuate a grove of stone as a memorial still of the first sanctuaries in which men worshipped.

"Against the clouds, far up the skies,

The walls of the cathedral rise,

Like a mysterious grove of stone."

Hence, also, the Druids, and the Druid temples, all were instances of the early purpose to which groves and forests were applied, that is, for worship; and when one thinks of the silence and the solemnity of primeval forests, one can see how naturally man would have recourse to them to worship; but when we see how sadly they were abused, one feels how easily the best things may be perverted, and God's own divine institutions turned into objects of sin and folly. But, blessed be God, neither in this mountain nor in that, neither in grove nor cathedral only, is worship acceptable to God. He is worshipped truly, and the worship is accepted, wherever He is approached in spirit and in truth.

(J. Cumming, D. D.).