I grew up with qawwali - the devotional music of South Asia. To this day, no other genre can make me feel the power of emotion intended by the poet. When amplified by the masterful voice control and crescending tone, it leaves you feeling - there is no other word - mast.
Although I am fluent in Urdu and proficient in Arabic, I am no translator. The terms used in Persian poetry have so much cultural, religious, and historic connotation that they defy translation. One might explain them but you lose the elegance of the original.
For example, the description used by the poet of detaching oneself, not caring about the entire universe, and finding a single, indivisible joy in sending blessings and prayers to the Prophet. These are sufiyana kalam - Sufi or mystical concepts. They make many orthodox Muslims uncomfortable - and extremists enraged - but perhaps the shock value of the borderline deification of the Prophet is part of the intended electric effect.
If you let the words sink in once you know their meaning, you'll eventually feel their meaning. Just like you're supposed to.
The lyrics are an adaptation of the poetry of Hafez, perhaps the world's best-known Persian poet. As is common in qawwali, the artists mix Arabic, Persian and Urdu together - which (to me) adds to its dramatic effect, even if people do not understand all three languages.
A big thank you to M. Tauseef Amin, who wrote the original lyrics into a YouTube video of the qawwali, and translated the Persian and Arabic into Urdu. My sister and I couldn't find an English version - so here goes.
* - Photo of Amjad Sabri used under CC 4.0 license MalikRizwan88, resized.