And We have enjoined on man (to be good) to his parents: in travail upon travail did his mother bear him, and in years twain was his weaning: (hear the command), "Show gratitude to Me and to thy parents: to Me is (thy final) Goal.
I said: Apostle of Allah! to whom should I show kindness? He replied: Your mother, next your mother, next your mother, and then comes your father, and then your relatives in order of relationship.
It is related by Umaamah radhiyallahu anhu that once a person asked the Apostle of Allah sallallaho alayhi wasallam, ‘How much is the claim of parents on their children?’ The Prophet sallallaho alayhi wasallam replied, ‘They are your Heaven and Hell.’ (Ibne Maajah)
Throughout the Qu’ran, and in numerous hadiths, our moral obligation to our parents—our obedience to them, our kindness to them is emphasized again and again.
Showing compassion and gentleness to our parents,has been stated in the quran along with the oneness and worship of Allah swt in such a way, that it seems to obey our parents…and to treat them with respect and kindness is next only to the divine worship of Allah swt.
*Thy Lord hath decreed that ye worship none but Him and that ye be kind to parents. Whether one or both of them attain old age in thy life say not to them a word of contempt nor repel them but address them in terms of honor.
And out of kindness lower to them the wing of humility and say: "My Lord! bestow on them Thy Mercy even as they cherished me in childhood.(17:23-24)*
Book 41, Number 5123:
Narrated AbuUsayd Malik ibn Rabi'ah as-Sa'idi:
While we were with the Apostle of Allah! (peace_be_upon_him) a man of Banu Salmah came to Him and said: Apostle of Allah is there any kindness left that I can do to my parents after their death? He replied: Yes, you can invoke blessings on them, forgiveness for them, carry out their final instructions after their death, join ties of relationship which are dependent on them, and honour their friends.