How does the tiebreaker against Green Bay work?

Kudos to our vikings defense yesterday. That is the best that they have looked probably since the 49ers game. I have directv and the
sunday ticket so I get all their games. I can't believe some of the
calls Moss gets or doesn't get; it oughta be a crime to be a ref in
the NFl when you see a penalty and don't throw the flag because you
don't like the player.
Anyway, my question is how does the tiebreaker work. If both teams
finish 5-1 in the division how will that determine who wins the
division? I know that overall record comes into play(I know that
pack will lose at least two more games)but lets say they finish the
year with the same record what then?
Looking for some knowledge.
Great win yesterday...I know it was the Lions but they needed it in a
bad way.
Peace out...[ba]