Musnad Abu Ya'la al-Mawsili 110:2

Ahmad ibn Jamil al-Marwazi narrated to us, Abdullah ibn al-Mubarak narrated to us, Rabah ibn Zayd informed us, from Umar ibn Habib, from al-Qasim ibn Abi Bazzah, from Sa'id ibn Jubayr, from Ibn Abbas, that he narrates that the Messenger of Allah (may Allah bless him and grant him peace) said: "Indeed, the first thing Allah created was the Pen, and He commanded it, so it wrote everything."