The central word in Hadewijch's writing is minne, which translates as love and behaves in her poems as a person and a force. Minne is not what the soul feels. Minne is what acts on the soul: she summons, she withholds, she demands total service, she wounds, she abandons, and the correct response to her cruelty is not complaint but more service. The vocabulary comes straight out of the courtly lyric of the period, the poetry of a knight bound to an unattainable lady, and Hadewijch takes it over whole and directs it at God.
That transfer is the technical achievement. Courtly love already had a fully worked language for unsatisfied desire, for fidelity under humiliation, and for a devotion that is proved by not being rewarded. Applied to God, it gives her an idiom for the experience she keeps returning to, in which nearness and absence are not opposites but two faces of the same relation, and in which the failure of consolation is evidence that the love is real rather than that it has failed.
She writes in three forms and they do a different job each. The Visions record extraordinary states and are the most extreme. The Letters are practical direction, written to younger Beguines, and are steadying, precise and frequently stern. The Poems in Stanzas carry the courtly machinery. Together they are among the first serious religious literature in any Dutch dialect, written by a woman at a time when a woman writing theology in the vernacular was itself a contested act.