Digested fitly to nutrition turn.
Open thy mind to what I now unfold,
And give it inward keeping. Knowledge comes
Of learning well retain'd, unfruitful else.

"This sacrifice in essence of two things
Consisteth; one is that, whereof 't is made,
The covenant the other. For the last,
It ne'er is cancell'd if not kept: and hence
I spake erewhile so strictly of its force.
For this it was enjoin'd the Israelites,
Though leave were giv'n them, as thou know'st, to change
The offering, still to offer. Th' other part,
The matter and the substance of the vow,
May well be such, to that without offence
It may for other substance be exchang'd.
But at his own discretion none may shift
The burden on his shoulders, unreleas'd
By either key, the yellow and the white.
Nor deem of any change, as less than vain,
If the last bond be not within the new
Included, as the quatre in the six.
No satisfaction therefore can be paid
For what so precious in the balance weighs,
That all in counterpoise must kick the beam.
Take then no vow at random: ta'en, with faith
Preserve it; yet not bent, as Jephthah once,
Blindly to execute a rash resolve,
Whom better it had suited to exclaim,
'I have done ill,' than to redeem his pledge