I looked at the NFL standings today, as well as the tiebreakers, to see what the Bears need to do in order to secure a playoff spot. In order to simplify things, i'm going to start by looking only at what we need to do in order to lock up the NFC North championship. The Bears are currently one game ahead of the Vikes with three games to play, the last of which is at Minnesota. However, we can clinch the division with wins in our next two games, even if the Vikes win the next two and stay a game behind us. If this happens, then lets assume the worst - that the Vikings win out, including a win against the Bears in week 17 to tie things up and make our head-2-head record 1-1. Since head-2-head is the first tiebreaker, the division determination would move to the 2nd tiebreaker, divisional record. If we beat Green Bay, and Minnesota beats us, we'll both be 5-1 against NFC North teams (with each team's loss coming against the other team). Then, we'd have to look at the 3rd tiebreaker - games against similar teams. We will have played 8 similar opponents out side the games in our own division, against the Bucs, Saints, Panthers, Falcons, Browns, Bengals, Steelers, and Ravens. In those 8 games, the Bears will be 5-3 (remember we're assuming they beat the Falcons), whereas the Vikings will be 4-4, even if they win their next 2 against the Steelers and the Ravens. Thus, the Bears would go to the playoffs even if they lost to the Vikings... as long as they win the next two games.
If we each lose one of the next 2, and the Vikings beat us to tie things up, whether or not we are division champs will depend on whether we lose to Green Bay or Atlanta. If we lose to the Packers and the Vikings, our divisional record will be 4-2, one game worse than the Vikings 5-1 record after beating us. Thus, the Vikes would go to the playoffs based off the 2nd tiebreaker. If we lose to the Falcons and the Vikings, we would go to the playoffs as long as the Vikings lose one of the two games leading up to our showdown, again off the 3rd tiebreaker, record against similar opponents.
If we both lose both our games leading up to our week 17 showdown, the Vikings will get the divisional crown if they beat us based off their better divisional record.
As you can see, if we want to make the playoffs, winning the Bears-Packers game is crucial. That win combined with any other win by the Bears or any other loss by the Vikings would clinch our first divisional title since 2001, as the only way the Vikings could beat us then would be by avoiding a tie, which would mean Bears losses to the Falcons and Vikings, and Vikings wins against the Bears, Steelers, and Ravens.