"To do justice and judgement is more acceptable to the Lord than sacrifice." (Prov 21:3)
Sacrifices and offerings are not bribes to make God overlook our character defects. It is the act of giving up something you want to keep. It is giving up something to help someone else. It is going without so that others won't have to.
Our Christian attitude and behavior must extend beyond the doors to the church. We cannot be the front row Christian and expect that our heavenly Father finds favor in our shoddy business dealings. Our tithes, what we do for others is not payment for our shortcomings. It is not payment for our sins.
If our personal and business dealings are not characterized by justice, there isn't any amount of generosity we render when that offering plate is passed that will make up for it. Lead a good life both in and out of the eyes of your Christian community. Be fair, be honest and then be generous!!!