An "extreme spiritualism"

 “Finally, as to the form of worship, Puritanism stands at the extreme of simplicity and meagreness. In this, also, it goes beyond Calvin. Even those symbolical forms and ancient church usages, which he either approved or at least tolerated as innocent, it rejects on account of their real or supposed connection with the abominated Catholicism; such as the cross, the altar, the clerical costume, all liturgical forms of prayer, and the church festivals even Christmas, Easter, and Whitsuntide. In the war against these things the Puritans displayed, in the days of Cromwell, the same pedantry and fanatism, nay, we may say the same formalism – only reversed, negative – as the Papists and Episcopalians in their zeal for them; and gave proof, that an extreme spiritualism, which overlooks the true import of the divinely created body, very easily passes unawares into its own opposite.” Philip Schaff, America, pp. 114-115