Ascetically

adv. [f. prec. + -LY².] After the manner of an ascetic.

c. 1800.  Miss Knight, Autobiog., I. 82. The Duke of Parma used frequently to clothe himself in a friar’s robe, and live ascetically.

1842.  J. H. Newman, Ch. of Fathers, 367. Nor live ascetically for the sake of them.