Bhai Harwans Tapa
Bhai Harwans Tapa used to serve in a Dharamshala (place of worship of Guru's devotees). He would feed the hungry disciples, wash the feet of tired disciples with warm water, massage their bodies, supply woollen blankets at night and provide hot water for bath early in the morning. In the morning he would recite Gurbani, and in the evening, the compositions of Bhai Gurdas ji.
Some of the disciples raised the issue that Guru ji had forbidden recitation of compositions other than Gurbani. So he requested Guru ji for clarification whether he should recite compositions of Bhai Gurdas ji or not? Guru ji said that some ignorant persons, out of jealousy had written some compositions against the principles of Gurbani. This was why their compositions were forbidden. But the compositions of Bhai Gurdas ji were the explanation of Gurbani. These compositions motivated one towards discipleship. The Lord's heart is Divine Knowledge and the Guru's heart is Gurbani. Thus, they can read the compositions of the disciples whose hearts are one with Gurbani (self-realized saints).
PS: Bhai Gurdas was one of the most eminent Sikh scholar, during the Guru period. A nephew of Guru Amardas ji, Bhai Gurdas ji was an exceptional parcharak of Sikhi. In addition to being Guru Arjan Sahib ji's scribe, during the dictation of the Guru Granth Sahib ji, his powerful words and understanding of Sikhi influenced many in diverse areas to become Sikhs. Bhai Gurdas ji's writings, preserved as vaars and kabiths, are given importance and sometimes referred to as the 'kunji' (key to understanding) of Gurbani