A base wisdom is full of ignorance. It encourages sin and evil deeds. The wisdom given by the True Guru is like the brightness of the day that pronounces righteous deeds.
With the emergence of Sun-like teachings of the True Guru, all that would stand in good stead becomes conspicuous. But consider any idol worship as dark night where one keeps wandering in doubts and suspicions by going wayward from the True path.
By the virtues of Naam obtained from the True Guru an obedient Sikh becomes capable of seeing all that is not visible openly or conspicuously. Whereas the followers of gods and goddesses remain manifested with evil or sinning vision.
The worldly people's association with gods and goddesses for acquiring worldly pleasures from them, is just like a blind person is holding on to the shoulder of a blind person in search of the right path. But those Sikhs who are united with the True Guru