http://www.energyenhancement.co.uk/BUDDHA.JPG 

"Each [omamori] mentions what temple or shrine it comes from,” and such notion of origin is important in Buddhist culture because returning to one’s origins reflects the Buddhist concept of the circle of life (Swagner).  The temple or shrine is also mentioned because, in Buddhism, one strays farther from enlightenment if one develops attachments to form or to material objects, whereas the shrine acts as a reminder of from whence the omamori came.  The shrine is a reminder of not just the place of origin, but based off of Buddhist teachings on the nature of non attachment, one could also interpret the place of origin as being a reminder to not become attached to the material, an item.

http://1sadieparish.wordpress.com/2013/11/30/dharma-karma-and-samsara/

Putting meaning into something allows the Buddha to manifest there. Thus, all objects have the potential of manifesting the Buddha, kami, or a sacred deity. Indeed, “[t]he Japanese have been willing to accept this world as absolute in the sense that it has been characteristic for them to perceive kami 神 as residing in all kinds of objects” (Swanger). An omamori manifests the Buddha and the sacred because we put the meaning unto it; it is not a sacred object because of its form, because ultimately the path to enlightenment is to transcend form itself and achieve the transcendence of attachment. Thus, one could argue that an omamori is sacred because we put meaning unto it and believe it to be sacred. Then, an omamori is a tool to discover the sacred, not so much as it is a sacred possession. Reader also discusses how many Japanese see omamori as a form of spiritual power that can manifest in our lives to save us from suffering. In the Mahayana Buddhist viewpoint, an omamori can be seen as a way of distributing the Buddha or Bodhisattva's cosmic energy as well as spirituality. These spiritual powers also can relieve people from suffering in that they enlighten one on the nature of suffering, as well as guide one down the correct path. Thus, they act to distribute karmic energy and benefits to those who need it from a higher celestial and enlightened being. 

 http://www.taleofgenji.org/saigoku_pilgrimage.html

The omamori allows us to be connected to Buddhism and also opens a sacred realm in our minds, clearing ourselves from bad fortune and negative energy.  This “notion of a transcendent presence existing over and above this realm [is such that] any place or object [including the omamori] could refract an otherwise unseen or unperceived dimension of existence” (Swanger). This connects to the concept that simply believing an object is sacred is what creates a sacred object, and there are examples of different objects that have been given sacred power simply due to the belief that they are sacred. “Both the belief in the immanent presence of numinal powers and the notion that they can be invited and persuaded to infuse specific objects appear to be prehistoric in Japan. Scarves, mirrors, swords, rocks, dolls and pillars are among the many objects which through the centuries have served as temporary abodes of the numina” (Swanger).