(Note: the reference is to church windows; this poem is part of Herbert's long sequence The Church, which in turn is part of The Temple, which contains most of his English poetry.)
LORD, how can man preach thy eternall word ?
He is a brittle crazie glasse :
Yet in thy temple thou dost him afford
This glorious and transcendent place,
To be a window, through thy grace.
But when thou dost anneal in glasse thy storie,
Making thy life to shine within
The holy Preachers, then the light and glorie
More rev'rend grows, and more doth win;
Which else shows watrish, bleak, and thin.
Doctrine and life, colours and light, in one
When they combine and mingle, bring
A strong regard and aw: but speech alone
Doth vanish like a flaring thing,
And in the eare, not conscience ring.
This poem seems relevant to much that is happening in the Church today. I got the text from the excellent Luminarium, which is a repository of a huge amount of English literature. The link is to the editor's account of how and why she began and continues the site.
Herbert's parish church:
Interior views of the church, and a good deal of information about Herbert, here.