Please comment upon the following quote from "Ode to the West Wind."
And, by the incantation of this verse, 65
Scatter, as from an unextinguish'd hearth
If Winter comes, can Spring be far behind? 70
The quote you have cited comes from the second half of the last stanza of this famous poem, and relates the imprecation of the speaker to be used by the West Wind to spread the kind of revolutionary energy and passion that the wind represents around the world. It is important to read this stanza in its entirety, so that images that are developed can be identified and understood. For example, the image of "ashes and sparks" to which the speaker comapres his words and verse can be matched with the idea of "withered leaves" that comes just before this quote. Both are images of apparent death and inanimate objects that can actually be used to spark new life, as the "ashes and sparks" can set fire and enflame other objects that they come into contact with.
The final lines represent a rather interesting shift in terms of the poet's perception of himself as he moves from viewing himself as a mere passive object being blown about by the wind like everything else to realising that he can be an instrument of the wind, the "trumpet of a prophecy," that can be used to convey a message to the world. The poem ends with the poet's hope that his words can be used in this way.