Musannaf Ibn Abi Shayba 33:1073

Waki’ narrated to us, from Sufyan, from Salamah ibn Kuhayl, he said: I heard Jundub al-’Alaqi saying: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever lets people hear [of his good deeds to show off], Allah will let [the people] hear [of his hypocrisy]. And whoever shows off, Allah will show off [his hypocrisy] through him."