Some nice references to tzedekah, some from the Bible, some from rabbinc literature. Tzekakah is the Hebrew word usually translated into English as righteousness but in judaism it means giving to the poor.
Here's some quotes, (the Biblical references are given using the Hebrew names for the books of the Bible, e.g. Devarim/Deuteronomy, Mishlei/Proverbs, Vayikra/Leviticus):
Pirkei Avot 2:8: Hillel used to say, The more tzedakah, the more shalom.
Ketubot 50a: A person shouldn’t give more than a fifth of his income [to tzedakah], lest he himself come to be in need of charity.
Ketuvot 68a: If a person closes his eyes to avoid giving [any] charity, it is as if he committed idolatry.
(That one reminds me of Colossians 3:5 (NIV)
5 Put to death, therefore, whatever belongs to your earthly nature: sexual immorality, impurity, lust, evil desires and greed, which is idolatry.")
Baba Bathra 9a: Charity is equal in importance to all other commandments combined.
Nedarim 81a: Do not neglect the children of the poor, for from them will go forth the Law.
Leviticus Rabbah 34:10: The blessing of tzedakah is greater for the person who gives than for the person who receives.
Tosefta Peah 4:21: Charity and lovingkindness intercede greatly and promote peace between Israel and their Father in Heaven.
Rabbi Nachman of Breslov: A person's drive for profit should be prompted by the desire to give tzedakah.
Proverbs 10:2: Treasures of wickedness will not avail, but charity will save from death.
(This one illustrates the differences in translation of tzedakah, Here's the NIV, Proverbs 10:2 Ill-gotten treasures have no lasting value, but righteousness delivers from death. The interpretation of that verse completely changes depending on who's definition of the Hebrew tzedakah you use.)
Bava Batra 10a: One who gives even a pruta (the least valuable coin) to the poor merits to receive the presence of G-d.
Here's the link, you have to scroll down and click on tzedakah.