Allah curses the one who curses his parents

We said to 'Ali b. Abi Talib: Inform us about something which Messenger of Allah ﷺ told you in secret, whereupon he said: He told me nothing in secret which he bid from people, but I heard him say: Allah cursed him who sacrificed for anyone besides Allah; and cursed him who accommodated an innovator; and Allah cursed him who cursed his parents and Allah cursed him who changed the boundary lines (of the land possessed by him).

أَخْبِرْنَا بِشَىْءٍ أَسَرَّهُ إِلَيْكَ رَسُولُ اللَّهِ ﷺ فَقَالَ مَا أَسَرَّ إِلَىَّ شَيْئًا كَتَمَهُ النَّاسَ وَلَكِنِّي سَمِعْتُهُ يَقُولُ لَعَنَ اللَّهُ مَنْ ذَبَحَ لِغَيْرِ اللَّهِ وَلَعَنَ اللَّهُ مَنْ آوَى مُحْدِثًا وَلَعَنَ اللَّهُ مَنْ لَعَنَ وَالِدَيْهِ وَلَعَنَ اللَّهُ مَنْ غَيَّرَ الْمَنَارَ

'Ali was asked whether Messenger of Allah ﷺ had showed special favour (by disclosing to him) a thing (which he kept secret from others). Thereupon he said: Messenger of Allah ﷺ singled us not for (disclosing to us) anything (secret) which he did not make public, (but those few things) which lie in the sheath of my sword. He drew out the written document contained in it and on that (it was mentioned): Allah cursed him who sacrificed for anyone else besides Allah; and Allah cursed him who stole the signposts (demarcating the boundary lines of the) land; and Allah cursed him who cursed his father; and Allah cursed him who accommodated an innovator (in religion).

سُئِلَ عَلِيٌّ أَخَصَّكُمْ رَسُولُ اللَّهِ ﷺ بِشَىْءٍ فَقَالَ مَا خَصَّنَا رَسُولُ اللَّهِ ﷺ بِشَىْءٍ لَمْ يَعُمَّ بِهِ النَّاسَ كَافَّةً إِلاَّ مَا كَانَ فِي قِرَابِ سَيْفِي هَذَا قَالَ فَأَخْرَجَ صَحِيفَةً مَكْتُوبٌ فِيهَا لَعَنَ اللَّهُ مَنْ ذَبَحَ لِغَيْرِ اللَّهِ وَلَعَنَ اللَّهُ مَنْ سَرَقَ مَنَارَ الأَرْضِ وَلَعَنَ اللَّهُ مَنْ لَعَنَ وَالِدَهُ وَلَعَنَ اللَّهُ مَنْ آوَى مُحْدِثًا