MECHTHILD of Magdeburg (1207-82) combined an outrageous bluntness with an overwhelmingly love-filled, mystical spirituality. In her twenties, she joined a group of Beguines (communities of women not bound by vows), and devoted herself to prayer, writing, peripatetic preaching, and caring for the sick.

She lambasted the ethical shortcomings of society with all the punch of the Old Testament prophets. Greed, sexual immorality, and gross idleness were endemic among the clergy, and she hit them hard: "The reason that God calls the cathedral clergy goats is because they reek of impurity regarding Eternal Truth before His Holy Trinity."

She was denounced as heretical, and her book, The Flowing Light of the Godhead, escaped the bonfire by a whisker. Undaunted, she rose to the attack. "I betook myself to prayer . . . then God commandest me to write." Not only was this bordering on blasphemy: it was a woman daring to thrust herself into the male-dominated field of medieval theology. The final insult came when she chose to write not in ecclesiastical Latin, but in the common parlance of Middle German. With one swift blow, this denuded the clergy of much of their mystique.

Mechthild's visions and unique relationship with God stirred up jealousy in her sister Beguines. She told them that God spoke of her tenderly, as "a light before my eyes, a lyre in my ears, a love in my life". It did not go down well, and she was despised, belittled, and excluded from the daily Offices and the celebration of mass. For her, this was an "exile of soul". Stress made her ill, and she went blind. The Cistercian nuns at Helfde took pity on Mechthild and incorporated her into their Order, where she found peace.

The Flowing Light of the Godhead is a compendium of visions, letters, and mellifluous spiritual poetry. It brims over with an ecstatic, reciprocal love of the Lord. She speaks of God as flowing in love, burning with ardent desire, and longing for union with her. He is the one who fills her heart, and to live without him is unthinkably bleak. In his reply, God likens her to a rose with thorns, and a bee seeking honey; and he promises that he will never turn away from her.

She was no stranger to the dark night of the soul: "A day is as a thousand years when you are absent." Time after time she fought her way through this seeming desertion by God until blessed light came again. God's love returned to her like a bird gliding through the air, hovering on the currents.

Her ethical stance resonates today. Consumerism, sexual exploitation, and a materialistic philosophy are not commensurate with the message of Christ. Her championing of women's equality echoes contemporary thinking in the Church. Mechthild's use of the common tongue is a reminder that the gospel message is not exclusively for the spiritual elite, but for all humanity. Today's world cries out for her belief that prayerful love can disempower evil and awaken us to the divine.

Perhaps what rings most in our ears after reading The Flowing Light of the Godhead is her prayer that captures so precisely the spirit of contemplation. "Wouldst thou know my meaning? Lie down in the Fire, See and taste the Flowing Godhead through thy being. Feel the Holy Spirit moving and compelling thee within the Flowing Fire and light of God."

Now that really does have the potential to boost our spiritual life.

The Revd David Bryant is a retired priest, living in Yorkshire.