"You can stick with a few clear-cut values, which are stronger than a multitude of values and will obviously yield a stronger painting. But not all subjects or light conditions appear that way... be sensible and paint with values that are appropriate and faithful to your subject."

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[It is appropriate that the Body and Blood of Christ be truly present in this Sacrament] because of the perfection of the New Covenant. The sacrifices of the Old Covenant contained the true sacrifice of Christ's Passion only in symbol....Therefore it was necessary that the sacrifice of the New Covenant, instituted by Christ, have something more, namely, that it contain Christ Himself who has suffered and contain Him not only in symbol but in reality.

— Thomas Aquinas