Muwatta Malik 988

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، كَانَ يَقُولُ اللَّهُمَّ لاَ تَجْعَلْ قَتْلِي بِيَدِ رَجُلٍ صَلَّى لَكَ سَجْدَةً وَاحِدَةً يُحَاجُّنِي بِهَا عِنْدَكَ يَوْمَ الْقِيَامَةِ ‏.‏

Yahya related to me from Malik from Zayd ibn Aslam that Umar ibn al-Khattab used to say, "O Allah! Do not let me be slain by the hand of a man who has prayed a single prostration to You with which he will dispute with me before You on the Day of Rising

Reference

Muwatta Malik 988

In-book

Book 21, Hadith 30