Shah Mahmud was now placed upon the throne; Vazir Fatah Khan was his prime minister, and Dost received the title of Sardar, or chief. It was about this time that the "Sardar of my tale," as the worthy Lal affectionately styles his hero, committed the first of a series of murders which, were there no other infamous deeds recorded of him, would stamp him as vile, and destroy any sympathy that his bravery in the field and notable talents might otherwise excite in his favour. A Persian secretary, one Mirza Ali Khan, by his skill and conduct as a politician, and by his kindly disposition, gained a popularity and influence which offended the ambitious brothers, and Fatah desired Dost to make away with him.
"On receiving the orders of the Vazir, Dost Mohammed armed himself cap-a-pie, and taking six men with him, went and remained waiting on the road between the house of Mohammed Azim Khan and the Mirza. It was about midnight when the Mirza passed by Dost Mohammed Khan, whom he saw, and said, 'What has brought your highness here at this late hour? I hope all is good.' He also added, that Dost Mohammed should freely command his services if he could be of any use to him. He replied to the Mirza that he had got a secret communication for him, and would tell him if he moved aside from the servants. He stopped his horse, whereupon Dost Mohammed, holding the mane of the horse with his left hand, and taking his dagger in his right, asked the Mirza to bend his head to hear him. While Dost Mohammed pretended to tell him something of his own invention, and found that the Mirza was hearing him without any suspicion, he stabbed him between the shoulders, and throwing him off his horse, cut him in many places. This was the commencement of the murders which Dost Mohammed Khan afterwards frequently committed."
Notwithstanding his high military rank and great services, Dost was very submissive to Fatah, who was greatly his senior. He acted as his cup-bearer, and was a constant attendant at his nocturnal carouses, carrying a golden goblet, and helping him to wine. The morals of both brothers were as exceptionable in private as in public life. Their biographer gives details of an intrigue between Dost and the favourite wife of Fatah; and even hints a doubt whether the Vazir was not cognizant of the intercourse, which he took no steps to check or punish. Both brothers were fond of wine, and indulged in it to excess. Dost, especially, was at one time a most unmitigated sot, although his bibulous propensities had apparently no permanent effect upon his intellects and energies. His capacity for liquor, if Lal's account be authentic, was extraordinary. "It is said that he has emptied several dozens of bottles in one night, and did not cease from drinking until he was quite intoxicated, and could not drink a drop more. He has often become senseless from drinking, and has, on that account, kept himself confined in bed during many days. He has been often seen in a state of stupidity on horseback, and having no turban, but a skull-cap, on his head." At a later period of his life, Dost Mohammed, being abroad one evening, met two of his sons, Afzal Khan, and the well-known Akhbar Khan, in an intoxicated state. Less tolerant for his children than for himself, he gave them a sound thrashing, and, not satisfied with that, took them up to the roof of a house, and threw them down on stony ground, to the risk of their lives. The mother of Akhbar heard of this, and reproached her husband with punishing others for a vice he himself was prone to. Dost hung his head, and swore to drink wine no more. We are not told whether he kept the vow, but subsequently, when he was made Amirul-Momnim, or Commander of the Faithful, he did forsake his drunken habits. On his reinstatement at Kabul, after its final abandonment by the British, he relapsed into his old courses, saying, that whilst he was an enemy to wine, he was always unlucky; but that since he had resumed drinking, his prosperity had returned, and he had gained his liberty after being in "Qaid i Frang," which, being interpreted, means an English prison. When sitting over his bottle, he can sing a good song, and play upon the _rabab_, a sort of Afghan fiddle, with very considerable skill. Altogether, and setting aside his throat-cuttings, and a few other peculiarities, Dost Mohammed must be considered as rather a jovial and good-humoured barbarian.