ʿAbd Al-Raḥmān b. Yazīd reports:
Al-Rabīʿ b. Khuthaym used to come to ʿAlqamah on the day of Jumuʿah and they would talk. They would call for me and I would come and talk with them. One day, they sent for me and I came. ʿAlqamah said to me,
Have you not heard what Al-Rabīʿ b. Khuthaym has come to us with? I replied,
And what is that? He said,
[Rabīʿ] said a man from the People of Scripture once said to us, I said,
Do you not see how much people supplicate but how seldom their prayers are answered? That is because Allāh does not accept except what is sincere and purely for Him.
Well ʿAbdullāh [b. Masʿūd] already said the same. He asked,
What did he say? I replied,
Haven’t you heard him say, He replied,
By Him other than whom there is none worthy of worship, Allāh does not accept [the deed] of one who seeks to be heard of, or seen, and nor someone who is playing around, [He only accepts the supplication] of one who calls upon Him from the bottom of his heart.
Indeed, [I have heard him say that].
Hunād b. Al-Sarī, Al-Zuhd #874.