The program of the Institute, the aim of the Institute, the possibilities of the Institute can be expressed in few words: the Institute can help one to be able to be a Christian. Simple!, That is all!" G.I.Gurdjieff, Views from the Real World.
Gurdjieff was through and through a Christian - he was born, raised and died one - and regarded the Teachings of Jesus Christ (distinct from the organisations that have evolved from it) as the best of all religions, both now and into the future.
He had claimed that the ideas and practices of original Christianity had been sustained in secret by communities in whom he had become acquainted during his travels. And while Scripture alluded to the "Why" and the "What" of the meaning and purpose of human existence, it was only the "How" that could breath into it life for people to live by.
Accordingly, the Work, as expressed by Gurdjieff, is at the heart of Christianity - meaning that, while Christ's life, death and resurrection initiated the possibility of a personal relationship with God (communion and union) that had not been possible before, the Work provides the way to help accelerate its actualisation.
The ideas and practices of the Work are wholly compatible - inwardly and essentially - with the Gospel of Christ.
Recommended reading is Joseph Azize's 2020 book - "Gurdjieff: Mysticism, Contemplation, and Exercises", Oxford University Press.