The Prophet ﷺ asked a man, "What do you say in your prayer?"The man replied, "I recite the tashahhud, then I say, 'O Allah, I ask You for Paradise and seek Your protection from the Fire.' I cannot match your soft murmuring, nor that of Muaz."The Prophet ﷺ said, "It is around these very matters that we murmur."
حدثنا عثمان بن أبي شيبة حدثنا حسين بن علي عن زائدة عن سليمان عن أبي صالح
قال النبي ﷺ لرجل كيف تقول في الصلاة قال أتشهد وأقول اللهم إني أسألك الجنة وأعوذ بك من النار أما إني لا أحسن دندنتك ولا دندنة معاذ فقال النبي ﷺ حولها ندندن
Its chain of transmission is daif. Ahmad reported it (3/474) through the hadith of Zaida, and the hadith has many corroborating narrations with Ibn Khuzayma, no. 725, and Ibn Hibban, no. 514, and others besides them. Amash is a mudallis and he narrated using "an" (indicating possible concealment in the chain), and the following hadith (793) makes it unnecessary.