The first question:
Shankaracharya teaches metaphysics and at the same time he sings the songs of the divine. Is there any interrelation between knowledge and bhakti, devotion?
Knowledge is negative, devotion is positive. Knowledge is like preparing the earth by removing the grass and the weeds and then putting in the manure, and devotion is like the sowing of the seed. Knowledge in itself is not sufficient. It cleans the earth, but the seeds cannot be sown. It is necessary, but not sufficient, because knowledge is of the mind and devotion is of the heart.
All the obstacles on the path of the divine can be removed by knowledge. But the steps of the stairs can be climbed only by devotion. That is why knowledge is negative. It is very effective in removing the meaningless but it is not able to create the meaningful.
Shankaracharya is talking about knowledge so that the layers of ignorance collected within you may be cleared away. And once the soil of the mind is cleared of all the unnecessary wild grass and plants, the seeds of devotion can be sown. Then it is possible to sing the song of the divine.
There is no contradiction between the two. Devotion is the culmination of knowledge and knowledge is the beginning of devotion, because man has both heart and mind, and both of them have to be approached, both of them have to be transformed. If you get stuck only in knowledge then you will be like a desert – very clean but nothing will grow there; clean but seedless; vast but without any height or depth.
Knowledge is dry and lonely. And if you remain a devotee, a bhakta only, then there will be trees, flowers and greenery in your life but you will not know how to protect that greenery. You will not be able to protect those plants. If anyone puts the seeds of doubt in your fertile soil, they will also sprout.
If a devotee has not passed through the process of knowledge then his building is going to be shaky. Anyone can put doubt in him. And he knows how to believe the believers, those who are leading him on the path, and he believes even those who are misleading him. He doesn’t have the sense of discrimination and discretion. He gets hold of the wrong in the same way as he gets hold of the right. The devotee is like a blind man and the knowledgeable person is like a lame man. If they both get together then things work out beautifully.
You must have heard this story.