PREPOSITIONS. For, transition into a conjunctionFor, in the sense of "because of," is found not only governing a noun, but also governing a clause:
i.e. "because I have had such faults."
“You may not so extenuate his offence
For I have had such faults.
So Othello, i. 3. 269; Cymb. iv. 2. 129. And parenthetically very frequently:
“('Tis ungrateful) to be thus opposite with heaven,
For (because) it requires the royal debt it lent you.
“The canker-blossoms have as deep a dye
As the perfumed tincture of the roses,
But for their virtue only is their shew,
They live unwoo'd, and unrespected fade.
i.e. to rob, "because we wish to be generous." With the future, for meant "in order that."
“Oh, it is as lawful,
For we would give much, to use violent thefts.
The desire of clearness and emphasis led to the addition of because. “But for because it liketh well our eyes.” N. P. Pref.
“And, for the time shall not seem tedious,
I'll tell thee what befel me.
Comp. "but only," "more better," &c. For, when thus followed by a verb, like after, before, &c. ("after he came," "before he went"), is called a conjunction. It is often, like other prepositions (287) thus used, followed by "that." Coriol. iii. 3. 93, &c. The two uses occur together in the following passage, which well illustrates the transition of for:
“And for because the world is populous.
“I hate him for he is a Christian,
But more for that . . . he lends, &c.