The aim of Qasidas or spiritual odes, of which this is a compendium, is to worship Allah, by turning men's hearts to the Divine, who says, "And when My servants ask you of Me, truly I am close" (Koran 2:186).
The purpose of qasidas in the Sufi path is to convey the experiential gnosis of forbearers to subsequent generations, for what comes from the heart goes into the heart, and most of the poets who wrote them were sheikhs of the tariqa who addressed their words to those with experiences like themselves, or to aspirants.
My own sheikh, 'Abd al-Rahman al-Shaghouri (Allah be well pleased with him), was a poet and the leader of his sheikhs' vocalists at the hadra or 'public dhikr' in Damascus for decades.
He once told me that the content of a qasida first comes as an experience from Allah, which the sufi poet afterwards tries to clothe in words. A poet thus distills the concentrated essence of his particular experience, from a lifetime of spiritual endeavor, into the words that make up the qasida.
To borrow a metaphor from the poets themselves, just as the universe is a 'goblet' for the beginninglessly eternal 'wine' of the Divine Oneness, which it conveys to human hearts by denoting, signifying, and portending it; so too does the goblet of a qasida convey to the heart of hearers the 'wine' experienced in the author's highest apprehensions of the Divine.
Sheikh 'Abd al-Rahman also told me that, quite apart from the words, the melody, tone, and delivery of a qasida also turn hearts to Allah, and he used to emphasize the need for vocalists to have, in some measure, had the experiences that the qasidas celebrate. In a word, the performance and spiritual state of the singers, with the rhythm of the accompanying group dhikr, harrows the earth of the heart, so it may absorb the rain of the spiritual intuitions conveyed by the qasidas.
Yet qasidas and spiritual experiences remain a means rather than an end. As Ibn 'Ata Illah said: "Do not extol a spiritual experience you do not yet know the result of, for the purpose of clouds is not that they send down rain. Their purpose is but that they bring forth fruit." The fruit here is that through experiencing the Divine Oneness, one's religion may no longer be merely for oneself, but wholly for Allah, in accordance with the nature of the relative and the Absolute. For experience is that which apprehends objective truth: here, the ultimately and abidingly Real.
The person who can benefit from these qasidas is someone whose way lies with the Prophet (Allah bless him and grant him peace), and whose heart lies with Allah.
Sheikh Nuh Ha Mim Keller