Reward of retaining spit in the mouth during Salaat

1. My father رحمه الله from Sa’d b. Abdillah from Ahmad b. Muhammad b. Ali b. Ahmad from Sahl b. Darihi from his father from Abi Abdillah عليه السلام who said: “One who retains his saliva during Salat out of respect of Allah’s Majesty and His Honor, Allah keeps him healthy till his death.”