Declaiming Waters none may dread — Teardrops

Declaiming Waters none may dread－¹
But Waters that are still
Are so for that most fatal cause
In Nature－they are full－

(F.1638/J.1595)

[1] Waters:: liquid from the mouth. Declaiming:: speaking loudly.
[2] Waters, still:: liquid from the eyes that are still shedding.
[3] Are so for:: tears are so shedding because of. most fatal cause:: the most extreme cause of tears, death, hinted by still, not moving.
[4] full:: fully occupied with the thought of (OED 3).