سنن أبي داود

Narrated Abu Hurairah: The Messenger of Allah (ﷺ) as saying: There are three people who Allah will not address on the Day of Judgement: a man who prevents traveller from the excess water which he has with him; and a man who swears for the goods (for sale) after the afternoon prayer, that is, (he swears) falsely; and a man who takes the oath of allegiance to a ruler (imam); if he gives him (something), he fullfils (the oath of allegiance) to him, if he does not give him (anything), he does not fulfill it.