He tells us himself that he entered upon public business in the time of the Phocian war, and the same may be collected from his Philippics. For some of the last of them were delivered after that war was finished; and the former relate to the immediate transactions of it. It appears, also, that he was thirty-two years old when he was preparing his oration against Midias; and yet at that time he had attained no name or power in the administration.…
He had a glorious subject for his political ambition to defend the cause of Greece against Philip. He defended it like a champion worthy of such a charge, and soon gained great reputation both for eloquence and for the bold truths which he spoke. He was admired in Greece, and courted by the king of Persia. Nay, Philip himself had a much higher opinion of him than the other orators; and his enemies acknowledged that they had to contend with a great man. For Aeschines and Hyperides, in their very accusations, give him such a character.
I wonder, therefore, how Theopompus could say that he was a man of no steadiness, who was never long pleased either with the same persons or things. For, on the contrary, it appears that he abode by the party and the measures which he first adopted; and was so far from quitting them during his life that he forfeited his life rather than he would forsake them.…
It must be acknowledged, however, that he excelled all the orators of his time, except Phocion, in his life and conversation. And we find in his orations that he told the people the boldest truths, that he opposed their inclinations and corrected their errors with the greatest spirit and freedom. Theopompus also acquaints us that when the Athenians were for having him manager of a certain impeachment, and insisted upon it in a tumultuary manner, he would not comply, but rose up and said, "My friends, I will be your counsellor whether you will or no; but a false accuser I will not be how much soever you may wish it.…"
Demosthenes, through the whole course of his political conduct, left none of the actions of the kin of Macedon undisparaged. Even in time of peace he laid hold on every opportunity to raise suspicions against him among the Athenians, and to excite their resentment. Hence Philip looked upon him as a person of the greatest importance in Athens; and when he went with nine other deputies to the court of that prince, after having given them all audience, he answered the speech of Demosthenes with greater care than the rest. As to other marks of honour and respect, Demosthenes had not an equal share in them; they were bestowed principally upon Aeschines and Philocrates. They, therefore, were large in the praise of Philip on all occasions, and they insisted, in particular, on his eloquence, his beauty, and even his being able to drink a great quantity of liquor. Demosthenes, who could not bear to hear him praised, turned these things off as trifles. "The first," he said, "was the property of a sophist, the second of a woman, and the third of a sponge; and not one of them could do any credit to a king."
Afterward, it appeared that nothing was to be expected but war; for, on the one hand, Philip knew not how to sit down in tranquillity; and, on the other, Demosthenes inflamed the Athenians. In this case, the first step the orator took was to put the people upon sending an armament to Euboea, which was brought under the yoke of Philip by its petty tyrants. Accordingly he drew up an edict, in pursuance of which they passed over to that peninsula, and drove out the Macedonians. His second operation was the sending succor to the Byzantians and Perinthians, with whom Philip was at war. He persuaded the people to drop their resentment, to forget the faults which both those nations had committed in the confederate war, and to send a body of troops to their assistance. They did so, and it saved them from ruin. After this, he went ambassador to the states of Greece; and, by his animating address, brought them almost all to join in the league against Philip.…
Meantime Philip, elated with his success at Amphissa, surprised Elatea, and possessed himself of Phocis. The Athenians were struck with astonishment, and none of them durst mount the rostrum; no one knew what advice to give; but a melancholy silence reigned the city. In this distress Demosthenes alone stood forth, and proposed that application should be made to the Thebans. He likewise animated the people in his usual manner, and inspired them with fresh hopes; in consequence of which he was sent ambassador to Thebes, some others being joined in commission with him. Philip, too, on his part, as Maryas informs us, sent Anyntus and Clearchus, two Macedonians, Doachus the Thessalian, Thrasidaeus the Elean, to answer the Athenian deputies. The Thebans were not ignorant what way their true interest pointed, but each of them had the evils of war before his eyes; for their Phocian wounds were still fresh upon them. However, the powers of the orator, as Theopompus tells us, rekindled their courage and ambition so effectually that all other objects were disregarded. They lost sight of fear, of caution, of every prior attachment, and, through the force of his eloquence, fell with enthusiastic transports into the path of honour.
So powerful, indeed, were the efforts of the orator that Philip immediately sent ambassadors to Athens to apply for peace. Greece recovered her spirits, whilst she stood waiting for the event; and not only the Athenian generals, but the governors of Boeotia, were ready to execute the commands of Demosthenes. All the assemblies, as well those of Thebes as those of Athens, were under his direction: he was equally beloved, equally powerful, in both places; and, as Theopompus shows, it was no more than his merit claimed. But the superior power of fortune, which seems to have been working at revolution, and drawing the liberties of Greece to a period at that time, opposed and baffled all the measures that could be taken. The deity discovered many tokens of the approaching event.