The Great Spirit is one of Okotos oldest "myths". Ekimu and Makuta were some of the largest believers in the GreatSpirit, they taught the Protectors all they knew of the scriptures, and then they taught their villagers and the villagers taught their children.
More Story: (If this breaks the rules just pretend it doesn't exist)
The GreatBeing created the elements. From the elements he forged Okoto. From the earth and water of Okoto he created us. There for we are Okoto and we must treat our home with as much respect as we would our neighbor.
Not everything the GreatBeing created was good and pure. With fire's warmth came it's rage, with stones strength came it's harshness, with water's love came it's persistent nagging, with ice's preservation came its sting, with jungle's beauty came it's confusion and with earth's support came its loneliness. (Knowing this mask maker where sure to never put more then one of the elements in a mask.)