Incarnation vs. Reincarnation: What's the Difference?

Because so many of my friends have asked me about this particular topic, I will discuss each separate issue and explain why it is that I believe that even though we had previous embodiment as spiritual beings in our first estate that we only incarnate into the flesh once.  I will share various scriptures to verify that those that incarnated into the flesh before us entered material form only once. [26] For then must he often have suffered since the foundation of the world: but now once in the end of the world hath he appeared to put away sin by the sacrifice of himself. [27] And as it is appointed unto men once to die, but after this the judgment: [28] So Christ was once offered to bear the sins of many; and unto them that look for him shall he appear the second time without sin unto salvation.Hebrews 9:27