Kabir Das was a popular 15th-century Indian mystic poet and saint having written hundreds of poems. These poems, translated into English by the great Indian poet Rabindranath Tagore, were first published in 1915. Here’s one of his poems where he talks about him being the slave of this Spirit of the quest.

Passage

O Friend! hope for Him whilst you live, know whilst you live, understand whilst you live: for in life deliverance abides.
If your bonds be not broken whilst living, what hope of deliverance in death?
It is but an empty dream, that the soul shall have union with Him because it has passed from the body:
If He is found now, He is found then,
If not, we do but go to dwell in the City of Death.
If you have union now, you shall have it hereafter.
Bathe in the truth, know the true Guru, have faith in the true Name!
Kabir says: “It is the Spirit of the quest which helps; I am the slave of this Spirit of the quest.”

Rabindranath Tagore. The Songs of Kabir. The Macmillan Company, 1915.