Muslim suicide bombers attacked the heart of liberal Islam yesterday with two deadly blasts at Pakistan’s most revered Sufi shrine, killing 41 people and injuring 175 more in an attack that appeared designed to inflame sectarian tensions.

Lahore is a sort of mecca for Sufism, the liberal, mystical arm of Islam that rejects the concept of jihad and promotes spiritual enlightenment through music and prayer.

A number of Sufis, who practice a mystical form of Islam, and Sufi groups on both US coasts entrusted millions of dollars to a California lawyer, Richard M. Glantz, who is a member of the Sufi community.

Sufi Order International, North America was invested in one of Glantz’s funds, which had a large portion of its estimated $17 million with Madoff.

Sufism is widely seen as a ‘kinder, gentler version’ of Islam, and is increasingly viewed as a possible way to combat the hard-line Islam of intolerant, hate-filled Muslim extremists.

Here’s a look at Sufism in Morocco, Iran, and Pakinstan.

Sufis are the power that has made Islam the world’s second-largest religion, with perhaps 1.2 billion adherents, writes Philip Jenkins, stating that “these dedicated defenders and evangelists of mystical Islam — are potentially vital allies for the nations of the West.”