Your seed does not improve God, it turnaround your dryness to a fountain of water. Sowing is an instruction which must be obeyed, to enter into your covenant right to prosperity. If you give with a free will, you will be blessed. You can give anything except your wife. Don't hold offense with anyone because you gave to him in the past. Your harvest most times will come from another source. Be patient while waiting for your harvest otherwise, it could be lost.