Sunan an-Nasa'i 1521

أَخْبَرَنَا مَحْمُودُ بْنُ غَيْلاَنَ، قَالَ حَدَّثَنَا وَكِيعٌ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ هِشَامِ بْنِ إِسْحَاقَ بْنِ عَبْدِ اللَّهِ بْنِ كِنَانَةَ، عَنْ أَبِيهِ، قَالَ أَرْسَلَنِي أَمِيرٌ مِنَ الأُمَرَاءِ إِلَى ابْنِ عَبَّاسٍ أَسْأَلُهُ عَنْ الاِسْتِسْقَاءِ، فَقَالَ ابْنُ عَبَّاسٍ مَا مَنَعَهُ أَنْ يَسْأَلَنِي، خَرَجَ رَسُولُ اللَّهِ صلى الله عليه وسلم مُتَوَاضِعًا مُتَبَذِّلاً مُتَخَشِّعًا مُتَضَرِّعًا فَصَلَّى رَكْعَتَيْنِ كَمَا يُصَلِّي فِي الْعِيدَيْنِ وَلَمْ يَخْطُبْ خُطْبَتَكُمْ هَذِهِ ‏.‏

It was narrated from Hisham bin Ishaq bin Abdullah bin Kinanah that:His father said: "One of the governors sent me to Ibn Abbas to ask him about the prayer for rain. He said: 'What kept him from asking me? The Messenger of Allah (ﷺ) went out humbly, (dressed) in a state of humility, submissiveness and beseeching, and he prayed two rak'ahs as in the Eid prayer, but he did not deliver a Khutbah like this Khutbah of yours

Reference

Sunan an-Nasa'i 1521

In-book

Book 17, Hadith 18