How much and where?

I have been thinking for sometime now to contribute financially to a organization whose primary focus is missions, as opposed to social works. The reason why I would like to give priority to the former rather than the latter is because I believe that Christ comes before personal welfare. If there is no Christ, any effort to feed the poor and tend the sick will be in vain. What use is there for one to be relieved of his sufferings for the short while he is on earth, only to face an even greater suffering upon death...

I'm not sure which organization to contribute to, and how much. This is something I'm still asking God about. I have to admit that I was initially very very very hesitant to ask Him "how much" for fear that He would give me a sum that is overly budget-unfriendly.

However, I have come to realize that to give financially is not just a way of giving back to Him, but also an avenue for me to learn to trust Him. By asking Him how much, I'm sticking my neck out... however much He says, I have to give and if by giving, I'm in any way put in a difficult situation, I have to trust that He will make it up in other ways.

"But you might ask, 'What will we eat during the seventh year, since we are not allowed to plant or harvest crops that year? Be assured that I will send my blessing for you in the sixth year, so the land will produce a crop large enough for three years." Leviticus 25:20-21