Whenever Harith al-Muhasibi stretched out his hand for food of dubious lawfulness, a nerve in the back of his finger became taut and the finger did not obey the command to move. Providence prevented Harith from eating food brought with the money acquired through usury, gambling or other means not permissible by Islam. Born in the year 781 AD in Basra, the great Sufi Muhasibi spent his life in Baghdad where he studied from the leading teachers of the time, the Arabic word Muhasaba, meaning someone who takes account. He was called Muhasibi due to his constant reckoning of himself. He also taught this method of Muhasaba, in anticipation of the Day of Reckoning through constant self-examination.
The famous Sufis such as Junayd of Baghdad and Sari Saqti were among Muhasibi’s students. He turned the queries of his students into books and these preserve a dialogical structure. It is said that he authored over a hundred books and treatises. His writings include the Kitab al Re’aya, containing the principles of Sufism. Imam Ghazali, the master of moderate mediaeval Sufism depended largely on the works of Muhasibi. He also authored Fasl fi Mohabba, another famed manual on the love of God. Muhasibi wrote that the clearest sign of divine love is that one should completely surrender to God with continuous meditation and prayer. However, the extent of this love depends on divine grace bestowed on the devotee. It is God who elevates the spirituality of a person. One who is humble and sincere in his devotion and has a good opinion of God is blessed with his grace.
Muhasibi’s writings focus on developing God consciousness that is necessary to know and serve God. He preached the relentless fight against man’s lower nature. He emphasises not just on the outward struggle of the ascetic against the flesh, but also a subtle psychological analysis of every thought along with uninterrupted spiritual training. He emphasises on both the inner and outer duties to God. He says: “Knowledge bequeaths fear, divestment from the world bequeaths comfort, and gnosis bequeaths self-criticism. One who does not thank God for a blessing has called for its eradication. The best person is one who does not allow his hereafter to preoccupy him from his worldly affair nor does he allow his worldly affair to preoccupy him from his hereafter.”
Muhasibi had serious political and doctrinal difference with Mamun, the caliph of Baghdad. This led to his persecution and he was forced to give up teaching. He migrated to Kufa. Later, he was allowed to return to Baghdad where he died in 857.