2 Corinthians 9 (KJV)

6 But this I say, He which soweth sparingly shall reap also sparingly; and he which soweth bountifully shall reap also bountifully.

7 Every man according as he purposeth in his heart, so let him give; not grudgingly, or of necessity: for God loveth a cheerful giver. 

When one gives, it should be from their heart willingly, not from pressure or bitterness.  Also, give from your heart.  Do not give just so that God can Bless you or that others will gift you back 
 ~ Karmen

8 And God is able to make all grace abound toward you; that ye, always having all sufficiency in all things, may abound (exist in large numbers or amounts.) to every good work:
9 (As it is written, He hath dispersed abroad; he hath given to the poor: his righteousness remaineth for ever.

10 Now he that ministereth seed to the sower both minister bread for your food, and multiply your seed sown, and increase the fruits of your righteousness;)
11 Being enriched in every thing to all bountifulness, which causeth through us thanksgiving to God.
12 For the administration of this service not only supplieth the want of the saints, but is abundant also by many thanksgivings unto God;
13 Whiles by the experiment of this ministration they glorify God for your professed subjection unto the gospel of Christ, and for your liberal distribution unto them, and unto all men;
14 And by their prayer for you, which long after you for the exceeding grace of God in you.
15 Thanks be unto God for his unspeakable gift.

When we give our tithes it should also help our Sisters and Brothers in Christ that are in need and it should be enough to give to the lost as well. It should win people over to Christ. Our generosity should towards one another. God will be glorified because people will be able to see him working through us via our giving with a willing heart towards one another ~ Karmen