Hadith: One may not combine in marriage a woman and her paternal aunt, or a woman and her maternal aunt

عن أبي هريرة رضي الله عنه مرفوعاً: «لا يجُمَعُ بين المرأة وعمتها، ولا بين المرأة وخالتها».
[صحيح] - [متفق عليه]

Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "One may not combine in marriage a woman and her paternal aunt, or a woman and her maternal aunt."
[Authentic hadith] - [Narrated by Bukhari & Muslim]

Explanation

The pure Shariah of Islam came with everything that is good and upright, and is against everything that involves harm and evil. It encourages affinity, love, and affection, and prohibits aloofness, severance of relations, and hatred. When Allah permitted polygamy due to the benefit it may entail, and given the fact that the wives' living together with the man usually causes enmity and hatred among them because of jealousy, for this reason Allah has prohibited marrying a woman and certain close relatives of hers, for fear of severing the relations between relatives. Allah has made it impermissible for a man to marry two sisters at the same time, to marry a paternal or maternal aunt and her niece as well, or any pair of women who, if it is supposed that one of them is a male and the other is a female, they would be prohibited from marrying each other due to blood relationship. This Hadīth restricts the general indication of Allah's statement (which means): {And lawful to you are [all others] beyond these.}