"On the Parables of the Mustard Seed," by Denise Levertov

Who ever saw the mustard-plant,
wayside weed or tended crop,
grow tall as a shrub, let alone a tree, a treeful
of shade and nests and songs?
Acres of yellow,
not a bird of the air in sight.

No, He who knew
the west wind brings
the rain, the south wind
thunder, who walked the field-paths
running His hand along wheatstems to glean
those intimate milky kernels, good
to break on the tongue,

was talking of miracle, the seed
within us, so small
we take it for worthless, a mustard-seed, dust,
nothing.
Glib generations mistake
the metaphor, not looking at fields and trees,
not noticing paradox. Mountains
remain unmoved.

Faith is rare, He must have been saying,
prodigious, unique —
one infinitesimal grain divided
like loaves and fishes,

as if from a mustard-seed
a great shade-tree grew. That rare,
that strange: the kingdom

a tree. The soul
a bird. A great concourse of birds
at home there, wings among yellow flowers.
The waiting
kingdom of faith, the seed
waiting to be sown.
 

+ Denise Levertov