Regarding the Tithe

(Regarding the Tithe, a repost from a while back...) 
A couple of recent questions from a friend...
Where does the old covenant 10% tithe fit in the new covenant message of Grace?
My thought is that the tithe was a picture of us being set apart into Christ, the body of Christ. We know that the Law was a shadow that found it's substance, it's fulfillment in Christ. Once the substance of the shadow had come (was fulfilled) the tithe (shadow) is no longer needed. It would be like us continuing to make sacrifices even though the perfect sacrifice was made once and for all. It would be like our gaze following the shadow to the one casting the shadow but then continuing to look at the shadow.
Is it a faith issue for churches when it comes to tithing (can God really provide everything we need?)
It is definitely an issue for me in my relating about finances with Grace Life. Who is to say that the practical need has to be met? What if God decides it is time for the church, as it is known in a particular expression, to cease? But my lack of belief in His ordering our steps just drives me back to His sufficiency and away from mine. drives me back to His version of outcomes and the knowledge that I can't screw it up. That is why as a pastor I am forced to hold Grace Life with an open hand or go crazy with my fleshly control. 
It has to be God showing up for a pastor to give up control and the "right" for a particular appearance of a church to continue. Especially... if you are a pastor who’s significance, salary and insurance are tied to the church continuing. I respect pastors who find themselves in this position and STILL proclaim the fulfillment of the shadow, this sharing of risky Truth has to be in the strength of Christ. Holding the church with an "open hand" is the only way pastors will not use every tool of manipulation to get people to give their money to a church, including the tithe. What if instead of bringing the Law back a pastor instead said, "Hey we need this… amount of money if we want to continue as we are now. If you share our vision... give to it." Seems to be kind of simple.