He dealt largely in the stock of the tax-companies; he lent money to cities in several provinces; he lent money to Ptolemy Auletes, King of Egypt, both before he was expelled from his kingdom by sedition, and afterwards when he was in Rome in 59 and 58, intriguing to induce the senate to have him restored.

Rabirius never doubted that he would be so restored, and seems to have failed to see the probability of such a policy being contested or quarrelled about, as actually happened in the winter of 57-56.

He lent, and persuaded his friends to lend:[146] he represented the king's cause as a good investment; and then, like the investing agent of to-day who slips so easily from carelessness into crime, he had to go on lending more and more, because he feared that if he stopped the king might turn against him.
He had staked the mass of his substance on a desperate venture.

But time went on and Ptolemy was not restored, and without the revenues of his kingdom he of course could not pay his creditors.

At last, at the end of the year 56, Gabinius, then governor of Syria, had pressure put on him by the creditors--among them perhaps both Caesar and Pompeius--to march into Egypt without the authority of the senate.