Of > By; from still > ever, continually

5 Till envious men, fearing their rule's decay, 6 Gan coin strait laws to curb their liberty;

Gan > Did strait > strict

7 Yet sith they warlike arms have laid away,

sith > since

8 They have excelled in arts and policy,

policy > statecraft; sagacity, shrewdness

9 That now we foolish men that praise begin eke to envy.

That > [So that] praise > virtue, merit, praiseworthiness eke > also envy > begrudge, resent

302.3