It is desirable in Islam that everyone should be imbued with the spirit of charity. On all occasions he should be ready to give alms. The Prophet of Islam once observed that every Muslim is exhorted to give alms. When asked if the person concerned did not have anything to give, the Prophet replied he should work and earn and then he should keep some of his earnings for himself and give the rest to others. Then again he was asked what the person should do if he was unable to earn. The Prophet said, then he should help the needy. Again he was asked what he should do if he couldn’t help the needy. The Prophet replied, he should urge others to do good. He was asked what if he could not do this either. Then the Prophet observed that he should refrain from doing evil as that is also a form of charity. (Sahih al-Bukhari, Hadith no. 1445)

Alms-giving is not an occasional act. It has to be performed with regularity. When this spirit of charity is born within one it finds expression at all times. One who possesses this charitable spirit will surely act in accordance with it.

Charity in fact, expresses well-wishing for others. When this spirit of well-wishing is awakened, a person feels the inner compulsion to help others. If he has money he will help others with it. If he does not have money, he will earn some so that he may meet his own requirements and then give the rest to others. And if he does not have money, he will try to help others with his other capabilities, for instance, removing thorns from the path, or guiding travellers. This feeling will sometimes express itself in the form of urging others to do good. To reform others, he will say good words to them. The last form of charity is that he should save others from such of his actions as may harm them.

Source: A Simple Introduction to Islam