“Believe
in Allah and His Messenger, and spend in charity out of the substance
that he has given you as his trustee. For, those of you who believe and
spend in charity; for them is a great Reward” 57:7

Hadrat Abu Huraira (may Allah be pleased with
him) reported Allah's Messenger (may Allah's blessings and peace be upon
him) as saying, "Among the actions and good deads for which a believer
will continue to receive reward after his death are knowledge which he
taught and spread, a good child whom he left behind, a copy of the
Qur'an which he left as a legacy, a mosque he built, a house which he
built for the traveler, a stream which he caused to flow, or a sadaqa
which he gave from his property when he was alive and well, for which he
will continue to receive reward after his death." (Ibn Majah and
Baihaqi)

"Whosoever digs a well will receive reward for
that from Allah swt on the Day of Judgement when anyone amongst jinn,
men and birds drink from it " (bukhari and muslim)

Prophet Muhammad said, “When a man dies his
actions come to an end except for three: an ongoing charity; knowledge
that benefits others, or pious offspring who pray for him”. He also said
“Sadaqa is due on every joint of a person, every day the sun rises.
Every good act is sadaqa. Your smiling to your brother is sadaqa; an
exhortation of your fellowman to virtuous deeds is equal to alms-giving;
your putting a wanderer on the right road is sadaqa; your assisting the
blind is sadaqa; your removing stones, and thorns, and other
obstructions from the road is sadaqa; your giving water to the thirsty
is charity, and every step that you take towards prayer is a sadaqa.

"O believers, never shall you attain to true
piety unless you spend on others out of what you cherish yourselves; and
whatever you spend - verily, God has full knowledge thereof” 3:92.