1 Corinthians 12:25. So that there should be no division in the body, but that its parts should have equal concern for each other. 26 If one part suffers, every part suffers with it; if one part is honored, every part rejoices with it. N.I.V.
A person with a problem in his body will not be able to work as well as someone who is well, because this causes the rest of the body to be weakened. The same is true of the church. The people who are not tithing are spiritually sick, because they are affected by a curse that they have walked into, see Malachi 3:9. The efficiency of the entire body of Christ, is affected, because you can spiritually affect others. The weights that are holding most churches from accomplishing the goals God has for them, are not what you would call gross sins. They are disobedience to God’s Word concerning tithing. God will be able to use you a lot more, if you become obedient in tithing.