These quotes are attributable to Ali ibn Abi Talib, who was a military, political and religious leader in Arabia during the 7th Century. The quote in the title is something that struck me as being intuitively true, when I first read it.
“He who busies himself with things other than improvement of his own self becomes perplexed in darkness and entangled in ruin. His evil spirits immerse him deep in vices and make his bad actions seem handsome.”
"Authority, power, and wealth do not change a man; they only reveal him"
"Dislike in yourself what you dislike in others."
Ali ruled the Rashidun Caliphate from 656 to 661, and was the cousin of Mohammed. The above picture is just an artists rendition of what he may have looked like, as there was no tradition of portraiture at this time.
Bayon.