Guru Nanak, upon his enlightenment, believed that “there is no Hindu, nor Mussalman [Muslim],” and his teachings centered on the fatherhood of God and the brotherhood of all mankind, and loving others as such. Guru Nanak taught against the caste system as well as idol worship.
Guru Nanak is not known for being connected with the practice of yoga or meditation. Traditionally, yoga has not been an accepted practice in Sikhism, and there is a strongly-held belief among some mainstream Sikhs that yoga is incompatible with their religion. However, there are those who cite "Gurbani" (Sikhism's holy texts) to support yoga as an accepted practice, specifically yoga's goal of union with the Divine.