It is narrated from Sulayman ibn Hafs al-Marwazi that Imam al-Ridha عليه السلام wrote to him, saying: “In the prostration of gratitude (Sajdat al-Shukr), say one hundred times: ‘Thankfulness, thankfulness (Shukran, Shukran),’ and if you wish, say: ‘Pardon, pardon (Afwan, Afwan).’”