The Collaborative International Dictionary
To advantage one's self of
Advantage \Ad*van"tage\, v. t. [imp. & p. p. Advantaged; p. pr. & vb. n. Advantaging.] [F. avantager, fr. avantage. See Advance.] To give an advantage to; to further; to promote; to benefit; to profit.
The truth is, the archbishop's own stiffness and
averseness to comply with the court designs, advantaged
his adversaries against him.
--Fuller.
What is a man advantaged, if he gain the whole world,
and lose himself, or be cast away?
--Luke ix. 25.
To advantage one's self of, to avail one's self of. [Obs.]