The letter Gimmel stands, among other things, for Gemilut Chassadim, acts of loving kindness. The Talmud describes the relationship between acts of loving kindness and charity, and the ways in which loving kindness can be superior to charity. From all of this we learn that the way to have a lot is to give a lot. True wealth comes from being able to help others through both charity and kindness.
"Our Rabbis taught, In three respects is Gemiluth Hasadim superior to charity: charity can be done only with one's money, but Gemiluth Hasadim can be done with one's person and one's money. Charity can be given only to the poor, Gemiluth Hasadim both to the rich and the poor. Charity can be given to the living only, Gemiluth Hasadim can be done both to the living and to the dead. -Sukkah 49b"
"Gimmel Dalet, show kindness to the Poor [Gemol Dallim]. Why is the foot of the Gimmel stretched toward the Dalet? Because it is fitting for the benevolent to run after (seek out) the poor. And why is the roof of the Dalet stretched out toward the Gimmel? Because he, the poor, must make himself available to him. And why is the face of the Dalet turned away from the Gimmel? Because he must give him help in secret, lest he be ashamed of him. -Shabbath 104a"