According to Chapter 37, why is the earth-world considered more important than the heavenly world for spiritual progress?

Chapter 37 presents a compelling argument for the profound importance of the earth-world over a heavenly abode. It explains that heaven is merely a place for sensual enjoyment, from which one inevitably falls after their accumulated merit is exhausted. The text provocatively states that the quality of sensual pleasure is the same for Indra in his celestial garden as it is for a donkey in a dung-heap. In contrast, as Chapter 37 clarifies, the earth-world, despite its fleeting nature, offers a unique opportunity. Even a momentary life on earth allows one to offer every action to God, which can lead to attaining the place of fearlessness, a permanent spiritual achievement not guaranteed by a temporary stay in heaven.