Hello Amanda
That is a subject with an incomprehensibly broad scope. It could mean almost anything, such as Philosophy, Theology, Religious Doctrines, personal practices such as prayer, meditation, reflection, a walk in a beautiful countryside etc.
I discuss "spirituality" and spiritual or religious topics sometimes as "lesson" material.
I am not sure that this has a precise definition.
Moreover, all of our daily life experiences, whether Joyous, Tragic or Mundane, can fall within the classification of "Spiritual Lessons".
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