Giving charity is such an important part of Islam that even the Arabic word tasaddaqa (to give charity) comes from the root sadaqah meaning to speak the truth, and to be sincere. Sadaqah (voluntary charity) is different from Zakah, the compulsory alms that are collected every year.

A Muslim shows his sincerity of faith and attains piety by being generous: “By no means shall you attain Al-Birr (piety) unless you spend (in Allah’s cause) of which you love; and whatever of good you spend, Allah knows it well.(3:92)
There are dozens of verses in the Qur’an in which Allah tells Muslims to give in charity. Sometimes this charity is in expiation for wrongdoing, and other times it is an acknowledgment that everything one “owns” is in fact a trust from Allah and that anything spent in the way of Allah will be paid back in full and multiplied on the Day of Judgment. In fact, the Qur’an in places calls this spending “a beautiful loan.”

Muslims are enjoined to give charity without reproach to the recipient. It is also better for them to give secretly rather than openly so that their intention is entirely to gain the pleasure of Allah and not to gain the admiration of people. It is easy to give money as charity when one is wealthy, but the best charity is given when one fears poverty, for one must then sincerely trust in Allah’s reward. When Prophet Muhammad (peace be upon him) was asked which charity is best, he replied, “That you should give charity (in a state when you are) healthy, closefisted, haunted by the fear of poverty and hoping to become rich (charity in such a state of health and mind is the best).
 
And you must not defer (charity to such a length) that you are about to die and would be saying: This is for so and so, and this is for so and so. Lo, it has already come into (the possession of so and so).(Reported by Muslim)

Even the money that a person spends on his family counts as charity if his intention is for Allah. The Prophet (peace be upon him) said, “When a Muslim spends on his family seeking reward for it from Allah, it counts for him as charity.(Reported by Muslim)

There is a reward for good deeds done with no expectation of remuneration in this life.

And a woman may give charity of her husband’s earnings. A’ishah, the wife of the Prophet (peace be upon him) reported that the Prophet (peace be upon him) said: “When a woman gives in charity some of the food in her house, without causing any damage, there is a reward for her for whatever she has given, and a reward for her husband for what he earned. The same applies to the trustee. In no respect does the one diminish the reward of the other.(Reported by Muslim)

In fact, Prophet Muhammad (peace be upon him) told his followers that sadaqah (voluntary charity) is incumbent upon them every single day. But this sadaqah can take many forms: “There is a (compulsory) sadaqah (charity) to be given for every joint of the human body (as a sign of gratitude to Allah) every day the sun rises. To judge justly between two persons is regarded as sadaqah, and to help a man concerning his riding animal, by helping him to mount it or by lifting his luggage onto it, is also regarded as sadaqah; and (saying) a good word is also sadaqah, and every step taken on one’s way to offer the compulsory prayer (in the mosque) is also sadaqah, and to remove a harmful thing from the way is also sadaqah.(Reported by Al-Bukhari and Muslim)

Thus, even those who have little or no extra money can give to charity. For them, there is still reward in good deeds done for the pleasure of Allah with no expectation of remuneration in this life.

The Prophet (peace be upon him) said, “Giving charity is obligatory upon each Muslim.” It was asked, “What do you say of him who does not find (the means) to do so?” He said, “Let him do manual work, thus doing benefit to himself and give charity.” It was asked, “What about one who does not have (the means) to do so?” He said, “Then let him assist the needy, the aggrieved.” It was asked, “What do you say of one who cannot even do this?” He said, “Then he should enjoin what is reputable or what is good.” He was asked, “What if he cannot do that?” He (the Prophet) said, “He should then abstain from evil, for verily that is a charity on his behalf.” (Reported by Muslim)

Muslims are also encouraged to establish an ongoing charity whose rewards they will continue to reap after their deaths. This can be knowledge that is passed on in a book or other form, fruit trees from which the poor may eat, or an endowment. Thus sadaqah, in whatever form, should be a part of the Muslim’s daily life.

Such charity strengthens the Muslim’s piety, turns his intentions toward his Creator, and spreads wealth and goodwill among the community.