Why are you here as a Human Being ?
Since the moment man came to his senses, the mind has kept him wandering around. Man has tried many means to bring his mind under control, and the result of this was that many different forms of mind control practices came into existence.
This also gave an avenue to cunning individuals to cheat humanity in many ways. The Brahminical Hindu priests and holy men of Sri Guru Nanak Dev Ji's time were leading this group of cunning men and they got people stuck in so many different practices, disguises and clever tricks that even if they wanted to come out of it, they would not have been able to free themselves of it even after death !
Thus in this hymn, Sri Guru Nanak Dev Ji explains that by following these blind Brahminical beliefs, the lost masses could not find peace of mind by going into the mountains and meditating. Neither would putting on fake costumes, disguises and clever tricks, or even by bathing at places of pilgrimages help. These practices can never still the wandering mind. Stuck in these fruitless practices, life goes to waste.
Peace of mind can only be obtained by attaching oneself to the true Guru, following his teachings and by inculcating in the mind, principles and good values taught by the Guru Ji. Only the True Guru can give us the taste of the nectar of God's name, which in turn will give us Eternal life and salvation. This is the ultimate goal of human existence.