The latest use of 'eager' as a verb quoted by the O.E.D. is from Mulcaster's Positions (1581), where the sense is that of imitating physically: 'They that be gawled ... may neither runne nor wrastle for eagering the inward'. The Middle English use is closer to Donne's: 'The nature of som men is so ... unconvenable that ... poverte myhte rather egren hym to don felonies.' Chaucer, Boëth. De Consol. Phil. In the Burley MS. (seventeenth century) the following epigram on Bancroft appears:
A learned Bishop of this land
Thinking to make religion stand,
In equall poise on every syde
The mixture of them thus he tryde:
An ounce of protestants he singles
And a dramme of papists mingles,
Then adds a scruple of a puritan
And melts them down in his brayne pan,
But where hee lookes they should digest