Analysis of Upon A Lowering Of Morning

Well, with the day I see the clouds appear,
And mix the light with darkness everywhere;
This threatening is, to travellers that go
Long journeys, slabby rain they'll have, or snow.
Else, while I gaze, the sun doth with his beams
Belace the clouds, as 'twere with bloody streams;
This done, they suddenly do watery grow,
And weep, and pour their tears out where they go.

Thus 'tis when gospel light doth usher in
To us both sense of grace and sense of sin;
Yea, when it makes sin red with Christ's blood,
Then we can weep till weeping does us good.