The first stanza portrays a metaphor between man and windows to act as a structure for the rest of the poem. In the very first line of the poem: Lord, how can man preach thy eternal word? the speaker is asking God himself, a question about how a normal man, thus established as a preacher, can speak for him. In the following line, the speaker uses the metaphor: He is a brittle crazy glass in an effort to compare man to fragile and cracked glass, stressing normal glasss likelihood to be weak and break. In the next three lines of the stanza, the tone shifts from a negative tone, established through the comparison of Man to a brittle crazy glass to a more formal tone, established through the speakers description of how man changes whilst in Gods temple. Herbert further describes this metaphor of man being a window by stating: Yet in thy temple thou dost him afford / This glorious and transcendent place / To be a window, through thy grace. This ultimately means that when man is in Gods temple God affords him to change from a fragile glass which does not reflect light properly because of its imperfections, to becoming a window. This glorious and Transcendent place refers to the temple in which God is affording man to change because of his will to become a preacher.
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n the second stanza Herbert starts by comparing the process of annealing with the process of salvation: But when thou dost anneal in glass thy story / Making thy life to shine within. The speaker is stating that when glass is annealed it makes one shine from within. In this case, the glass getting annealed is comparable to salvation because when glass gets annealed its basically getting repaired. This is similar to salvation because salvation is deliverance from sin and its consequences. Therefore, in order for one to shine from within they need to get annealed in reference to glass or salvationed in reference to actual humans. However, the process of being annealed is not limited, as Herbert switches from singular in the first stanza to plural in the second as he in the first becomes preachers in the second. In lines 8-9, the speaker presents the idea that the more the preacher grows or anneals the more that preacher will win and become rich with light and glory: The holy preachers, then the light and glory / More revrend grows, and more doth win. In the final line of the second stanza, the speaker explains that before one anneals and becomes rich with light and glory they are watrish, bleak, and thin, more characteristics of the average man which is cracked glass.