Srimad Bhagwat Purana is also known as Vangmay Swaroop of Sri Krishna. Vangmay Swaroop is a Sanskrit phrase that means that  the words, the sound of chanting/reading of this ancient Sanskrit by Ved Vyas ji, just listening to it, one can experience the full blossoming of Divinity within oneself. Sri Krishna, the most playful, joyful, loved and wise incarnation of Lord Vishnu, the intelligence that sustains and is present in every anu/atom of the universe becomes available to a devotee through the reading/listening of Srimad Bhagwat Mahapurana. The Mangalacharan is just a brief preface to it that a devotee sings in joy!