Julie, I had missed that "come and know--" was direct address. I have now italicized it. I am still resisting "nod" because it has its own ambiguities, as in the phrase "even Homer nods," which implies that he is sleepy and careless. I see the tilt of the brow as not so much a nod as a tilting sideways movement of the head, implying "get out of here." Here is what I assume is going on in the poem. The angel is opposed to anything that closes off possibilities. He sees the Second Coming as something that is happening now, and he demands total openness from others. Anyone who calls out to the angel for understanding and sympathy, help with their own petty burdens of living, is likely to get more than they bargained for. When they attract the angel's attention, he comes and wrestles with them to break them wide open. Rilke is constantly going for these "you must change your life" moments, often triggered by something that is beyond the human. Rilke is in favor of them.