To live a pure unselfish life, one must count nothing as one's own in the midst of abundance.

This quote means that if you want to have an unselfish life, you should not consider any material possessions or wealth as belonging to you. Instead, you should share what you have with others, even when you are surrounded by abundance. The idea is to live in a way that benefits others and strives to promote kindness, generosity, and compassion.