Make A Virtue Of Necessity Meaning

Example : c. 1595, William Shakespeare, Two Gentlemen of Verona, act 4, sc.1:  Indeed, because you are a banish'd man,  Therefore, above the rest, we parley to you:  Are you content to be our general?  To make a virtue of necessity  And live, as we do, in this wilderness?1906, George Bernard Shaw, Major Barbara, Preface:  Nietzsche, as I gather, regarded the slave-morality as having been invented and imposed on the world by slaves making a virtue of necessity and a religion of their servitude.