The Letter Sad 38:78. Juz 23, page 457.
وَإِنَّ عَلَيْكَ لَعْنَتِىٓ إِلَىٰ يَوْمِ ٱلدِّينِ٧٨
And lo! My curse is on thee till the Day of Judgment.
Sad 38:78, translated by Marmaduke Pickthall