sri guru gita contains a dialogue of lord shiva and parvati
The Guru Gita contains a dialogue of Lord Shiva and Parvati in which Parvati requests Lord Shiva to explain the Guru and his significance. In it, Lord Shankar describes what is Guru, its importance, method of worshiping Guru, benefits of studying Guru Gita etc.
How glorious is that Satguru who can be. It has been perfectly described in this Gurugita. The ability of the disciple, his dignity, behavior, discipline, etc. have also been shown to be complete. In this way, by going to the Guru's shelter, the disciple attains perfection and he himself becomes Brahmarupa. All his religions, iniquities, sins and virtues etc. are eliminated and the only conscious remains left, he becomes multiplied and metamorphosed which is his last speed. Wherever he reaches is his destination. This is his form which he attains.