At length the party opposed to Ptolemy found, or pretended to find, in certain sacred books, called the Sibylline Oracles, which were kept in the custody of the priests, and were supposed to contain prophetic intimations of the will of Heaven in respect to the conduct of public affairs, the following passage: _"If a king of Egypt should apply to you for aid, treat him in a friendly manner, but do not furnish him with troops; for if you do, you will incur great danger."_ This made new difficulty for Ptolemy's friends. They attempted, at first, to evade this inspired injunction by denying the reality of it. There was no such passage to be found, they said. It was all an invention of their enemies. This point seems to have been overruled, and then they attempted to give the passage some other than the obvious interpretation. Finally they maintained that, although it prohibited their furnishing Ptolemy himself with troops, it did not forbid their sending an armed force into Egypt under leaders of their own. _That_ they could certainly do; and then, when the rebellion was suppressed, and Berenice's government overthrown, they could invite Ptolemy to return to his kingdom and resume his crown in a peaceful manner. This, they alleged, would not be "furnishing him with troops," and, of course would not be disobeying the oracle. These attempts to evade the direction of the oracle on the part of Ptolemy's friends, only made the debates and dissensions between them and his enemies more violent than ever. Pompey made every effort in his power to aid Ptolemy's cause; but Lentulus, after long hesitation and delay, decided that it would not be safe for him to embark in it. At length, however, Gabinius, the lieutenant who commanded in Syria, was induced to undertake the enterprise. On certain promises which he received from Ptolemy, to be performed in case he succeeded, and with a certain encouragement, not very legal or regular, which Pompey gave him, in respect to the employment of the Roman troops under his command, he resolved to march to Egypt. His route, of course, would lie along the shores of the Mediterranean Sea, and through the desert, to Pelusium, which has already been mentioned as the frontier town on this side of Egypt. From Pelusium he was to march through the heart of the Delta to Alexandria, and, if successful in his invasion, overthrow the government of Berenice and Archelaus, and then, inviting Ptolemy to return, reinstate him on the throne.