There's more to giving than being nice. The world rotates on its axis, the galaxies and stars continue moving—because of giving. Nothing we own is really ours to begin with—G‑d gives to us so we can give to others.

Giving is a mitzvah and a responsibility. As such, it comes with its own set of dos and don'ts:

The Obligation:

You're walking down the street and someone asks for food. The mitzvah says, you have to give something. If he asks for money, you're allowed to make some inquiries to determine if he's legit. Nothing in your pocket? Show some empathy, provide some kind and uplifting words. In no case can you just keep on walking.

Nothing in your pocket? Show some empathyStandard Jewish practice is to give at least 10% of net income to charity. There's plenty written on what's considered net—and on when tuition fees and other mitzvah-related items can be deducted from the ten percent. Speak with your rabbi about your specific issues.

Since giving is a mitzvah, it doesn't just help others—it lifts you up as well. That's why we keep a pushka (charity box) on prominent display in home and office. Just drop a few coins in the pushka every so often, at least once a day.

The Recipient:

Give tzedakah (charity) to the needy, Torah schools, Jewish institutions, and/or humanitarian causes. A family member who is in difficult financial straits takes precedence over non-family. Likewise, local poor and charitable organizations take precedence over their faraway counterparts. And charitable causes in Israel take precedence over (non-local) charities in the Diaspora.

The Upshot:

No other mitzvah evokes as powerful a divine response as tzedakah. It makes sense: you take care of others, and G‑d takes care of you. Our sages taught that tzedakah brings atonement and protects against harsh heavenly decrees.