Sahih al-Bukhari Book 78, Hadith 9
My mother came to me, hoping (for my favor) during the lifetime of the Prophet. I asked the Prophet,
"May I treat her kindly?" He replied, "Yes." Ibn 'Uyaina said, "Then Allah revealed: 'Allah forbids
you not with regards to those who fought not against you because of religion, and drove you not out
from your homes, that you should show them kindness and deal justly with them.'.......(60.8)
Allah's Messenger (ﷺ) mentioned the greatest sins or he was asked about the greatest sins. He said, "To join partners in worship with Allah; to kill a soul which Allah has forbidden to kill; and to be undutiful or unkind to one's parents." The Prophet (ﷺ) added, "Shall I inform you of the biggest of the great sins? That is the forged statement or the false witness." Shu`ba (the sub-narrator) states that most probably the Prophet said, "the false witness."
"My mother who was a Mushrikah (pagan, etc.), came with her father during the period of peace pact between the Muslims and the Quraish infidels. I went to seek the advice of the Prophet (ﷺ) saying, "My mother has arrived and she is hoping (for my favor)." The Prophet (ﷺ) said, "Yes, be good to your mother."