CONJUNCTIONS. But with the subjunctive and indicativeBut, in all its uses, may be explained from the meaning of "out-take" or except. It is sometimes used (like and, see above) to except or "out-take" a whole clause, the verb being occasionally in the subjunctive.
i.e. "except or without thou love me."
“And, but thou love me, let them find me here.
Compare 1 Hen. VI. iii. 1. 34: "Except I be provoked." So
“And, but I be deceived, Signior Baptista may remember
We now use "unless" in this sense, and by a comparison of Wickliffe with Tyndale and Cranmer it will be seen that but was already often superseded by "except." But with the subjunctive is, however, more common in Early than in Elizabethan English. Sometimes without the subjunctive--
“Not without the prince be willing.
“And, but she spoke it dying, I would not
Believe her lips.
“And, but he's something stain'd
With grief that's beauty's canker, thou might'st call him
A goodly person.
“The common executioner
Falls not the axe upon the humbled neck
But first begs pardon.
“And, but infirmity hath something seized
His wish'd ability, he had himself
The lands and waters 'twixt your throne and his
Measured, to look upon you.