Musannaf Ibn Abi Shayba 33:389

Abu Khalid al-Ahmar narrated to us, from Muhammad ibn Ishaq, who said: My paternal uncle, Musa ibn Yasar, narrated to me that Salman wrote to Abu al-Darda’: "Indeed, there is a man in the shade of the Throne whose heart is attached to the mosques out of love for them."