40-15 Al-Hakim Abu Ali Al-Husayn ibn Ahmad al-Bayhaqi narrated that Muhammad ibn Yahya al-Sowli quoted on the authority of Muhammad ibn Yazid al-Nahvi, on the authority of Ibn Abi Abdoon, on the authority of his father
“When Al-Ma’mun pledged allegiance to Ar-Ridha’ (a.s.), Al-Ma’mun had him (a.s.) sit next to himself. Abbas - the orator - stood up, delivered a good speech and ended it with the following poem:People can’t live without the sun and the moonNow you are the sun and he is the moon.”