Here's a breakdown of when to capitalize "spirit":
Capitalize "spirit" when:
* It refers to a specific deity or supernatural being: For example, "the Holy Spirit" or "the spirits of the ancestors."
* It's part of a proper noun: For example, "the Spirit of St. Louis" (a plane), "Spirit Airlines," or "the Spirit of Christmas."
* It's used in a title: For example, "The Spirit of the Law."
Don't capitalize "spirit" when:
* It refers to the non-physical part of a person: For example, "He's a man of great spirit."
* It refers to a general feeling or attitude: For example, "The team played with a lot of spirit."
* It's used as an adjective: For example, "She has a spirited personality."
In general, if you are unsure whether to capitalize "spirit," it's best to err on the side of caution and use lowercase.