oblige
verb (used with object)
to require or constrain, as by law, command, conscience, or force of necessity.
Used to describe an action that will be fully completed or achieved by a specific point in the future.
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
By so doing, you will be all right in the middle, you will have your sides also well protected, and, besides, you will have obliged two friends instead of one.
From Rambles in Womanland by Max O'Rell