So, trying out a Paladin for the first time in the new release of AE, and I'm a little confused about the wording of "Faith and Magik"

I get either 1 ritual of OP 1 Ceremonial Magik and 1 rank in Ceremony

or

1 prayer of OP 1 Divine magik, and 1 rank in Entreaty for the divine dominion of my deity (Megalon)

Concerning the second option:

Does this mean I get 1 prayer of my choice, along with the entire divine dominion? Do I spend EPS like a mage to gain access to higher level OP?

What about the first option? could I get a bit of clarification on it? I'm not sure how well it compares to the second.

Thank Starric, alright got another question for you.

I'm currently looking over the secrets I need for the legendary paladin secret Exalted Host, and as I was looking over Untrammeled Faith, I saw I needed "Vow (at least 2 accepted by your religon)"

Does that mean I need to take the Vow secret twice? Also, it doesn't have any mechanics to it, what does Vow do?