A waster, according to the Holy Qur'an, is anyone who uses his wealth, position, lusts, wishes and the rest of the blessings Allah has given to him in the satanic way and in the deviant path, which is neither reasonable nor permissible.
When talking about the work and the fruits of sowing and how to spend wealth, Allah says:
“…and pay the due of it on the day of its reaping, and waste not by excess: for Allah loves not the wasters.” Qur’an 6:141
This means giving from agricultural production what Allah has determined is due to the poor; giving to the needy, the officials appointed over the zakat, and those whose hearts are made to incline (to Islam); buying slaves and setting them free; paying the debts of needy debtors and giving to the wayfarers what is to be spent in the way of Allah. We should not be stingy with these monies nor should we waste them.
The Holy Qur'an talks about those who use their wealth, positions and powers in the way of injustice, oppression and aggression to frighten and threaten people and to achieve their low aims. Allah says:
“…and most surely Firon (the Pharaoh) was lofty in the land; and most surely he was of the extravagant.” Qur’an 10:83
The Holy Qur'an also talks about the people who are not chaste, who do not refrain from prohibited lusts, who do not know save material and bodily pleasures and who do not refrain from any aggression and vice to satisfy their sexual lusts. The Holy Qur'an says:
“Most surely you come to males in lust instead of females; nay you are extravagant people.” 7:81
The Holy Qur'an shows the humility and good end of the believers who submit to the Prophets (s) and their miracles, and, on the other hand, it shows the state of people who become haughty, proud and resistant before the clear proofs and true evidences and who prevent people from the Straight Path of Allah. Allah says:
“Then we fulfilled the promise unto them. So we delivered them and whom We would, and We destroyed the prodigals.” Qur’an 21:9
source : REPENTANCE THE CRADLE OF MERCY By Husayn Ansariyan