Fiqh-us-Sunnah Volume 3, Zakaat and Fasting, Fiqh 3.101.

It is unlawful for the one giving sadaqah to remind the recipient of his generosity, to reproach him, or to make a show with his sadaqah. Allah warns: “O you who believe! Do not invalidate your sadaqah by reminders of your generosity or by injury, like those who spend their property to be seen by men” [al-Baqarah 264].

The Messenger of Allah, upon whom be peace, said: “There are three [types of people]. Allah shall not speak to them, notice them, or sanctify them; and for them is a grievous penalty.” Abu Zhar inquired: “O Messenger of Allah, who are the ones gone wrong and astray?” He replied: “Those who through conceit lengthen their garments to make them hang on the ground, who give nothing without reproach, and who sell their merchandise swearing untruthfully [to its quality].”