A brayer is a thorny shrub and this image is visceral because even this plant, this piece of nature that Blake adores so much is used against him by the church to cause him agony.

荆棘是一种多刺的灌木，这个形象是发自内心的，为即使是这种植物，这种布莱克如此崇拜的自然景，教会用来对付他，给他带来痛苦。