All 7 Uses of

oblige
in
Moby Dick

"Elijah," said I, "you will oblige my friend and me by withdrawing.†
Chpt 19-21

oblige = grant a favor

"Anything to oblige ye, my sweet and pleasant fellow," rejoined Stubb, and with that he soon mounted to the deck.†
Chpt 91-93 *

In short, like many inland reapers and mowers, who go into the farmers' meadows armed with their own scythes—though in no wise obliged to furnish them—even so, Queequeg, for his own private reasons, preferred his own harpoon.†
Chpt 13-15

But as all my remonstrances produced no effect upon Queequeg, I was obliged to acquiesce; and accordingly prepared to set about this business with a determined rushing sort of energy and vigor, that should quickly settle that trifling little affair.†
Chpt 16-18

The weather was very clear and fine, but so intolerably cold that we were obliged to keep on our fur clothing.†
Chpt 43-45 *

Some fifty years ago there was a curious case of whale-trover litigated in England, wherein the plaintiffs set forth that after a hard chase of a whale in the Northern seas; and when indeed they (the plaintiffs) had succeeded in harpooning the fish; they were at last, through peril of their lives, obliged to forsake not only their lines, but their boat itself.†
Chpt 88-90

To which my Lord Duke in substance replied (both letters were published) that he had already done so, and received the money, and would be obliged to the reverend gentleman if for the future he (the reverend gentleman) would decline meddling with other people's business.†
Chpt 88-90

Definitions:

(1) (oblige as in: I am obliged by law.)
require (obligate) to do something
(2) (oblige as in: I obliged her every request.)
grant a favor to someone
(3) (obliged as in: I'm much obliged for your kindness)
grateful or indebted
(4) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Much more rarely, in classic literature you may see oblige as a synonym for ask as when Jules Verne wrote "I obliged the Professor to move his lamp over the walls of the gallery," in Journey to the Center of the Earth.