Paragraph 69

In plain words

"After the knowledge of Brahman, after samadhi, some come down again and keep the 'I of knowledge' or else the 'I of devotion.' When the market is over, some stay on in it as they please, Narada and others like him. They keep the 'I of devotion' to teach the world. Sankaracharya kept the 'I of knowledge' to teach the world.