Does "be thou me" mean "may/pray that you will be me"?

Context:

At last, Shelley again calls the Wind in a kind of prayer and even wants him to be ‘his’ Spirit: he says: ‘My spirit! Be thou me, impetuous one!’ (l. 62). Like the leaves of the trees in a forest, his leaves will fall and decay and will perhaps soon flourish again when the spring comes. That may be why he is looking forward to the spring and asks at the end of the last canto ‘If Winter comes, can Spring be far behind?’ (l. 70). This is of course a rhetorical question because spring does come after winter, but the "if" suggests that it might not come if the rebirth is strong and extensive enough, and if it is not, another renewal—spring—will come anyway. Thus the question has a deeper meaning and does not only mean the change of seasons, but is a reference to death and rebirth as well. It also indicates that after the struggles and problems in life, there would always be a solution. It shows us the optimistic view of the poet about life which he would like the world to know. It is an interpretation of his saying 'If you are suffering now, there will be good times ahead.' But the most powerful call to the Wind are the lines: "Drive my dead thoughts over the universe/like withered leaves to quicken a new birth!" Here Shelley is imploring—or really chanting to—the Wind to blow away all of his useless thoughts so that he can be a vessel for the Wind and, as a result, awaken the Earth.