Purview, Marvel, Boons : What is "Motifs"?

I don’t understand the concept of "motif" in Scion: Hero p236-237

For example:

  • I’m a Scion of Ares, and I want to use a Marvel of my War Purview to "Bless" me for combat. As written p237, the Theoi motif is "The most high may grant their favor to those who beseech them." What should i do, concretely ?

  • I’m a Scion of Susano-oo and want to use the "Flight" boon. As written p237, the Kami motif is "The kami are all things, and can be bidden to work wonders." What should i do, concretely ? Is Motif even required for purchased boon ?

  • I’m a Scion of Hel, with the Passion (Fear) purview. As specified p256, I could create a motif based on Fear. How this works concretly ?