Of course we know that the Bible tells us to give a tithe (one tenth) of our income to our local church, and offerings after the tithe to worthy causes (Mal. 3:10-11).

There are at least four reasons you'll have more after you give:
  1. The Bible teaches that giving is like planting a seed. Every seed produces a huge multiplication of its kind (2 Cor. 9:10).
  2. God promises to open heaven's windows and pour out blessings that you cannot possibly contain (Mal. 3:10).
  3. Other people are naturally (and supernaturally) compelled to bless those who are unselfish in their giving (Luke 6:38).
  4. Giving puts your faith in action, and faith is always rewarded abundantly by God (Heb. 11:6).
Source: Every Teenager's Little Black Book of Hard to Find Information
by Blaine Bartel.
Excerpt permission granted by Harrison House Publishers