عن شداد بن أوس رضي الله عنه أنه سمع النبي صلى الله عليه و سلم يقول من صام يرائي فقد أشرك ومن صلى يرائي فقد أشرك ومن تصدق يرائي فقد أشرك رواه البيهقي من طريق عبد المجيد بن بهرام عن شهر بن حوشب (الترغيب والترهيب 1/80)
Hadhrat Shaddaad bin Aus (Radhiallahu Anhu) reports that he heard Rasulullah (Sallallahu Alaihi Wasallam) say: “The one who fasts for show has ascribed partners with Allah Ta’ala (in the ibaadat of fasting). The one who performs salaah for show has ascribed partners with Allah Ta’ala (in the ibaadat of salaah). The one who gives wealth in charity for show has ascribed partners with Allah Ta’ala (in the ibaadat of charity).
Note: Though one will not come out of the fold of Islam through such sins, however due to carrying out this ibaadat without sincerity, the ibaadat will be rejected as it is not done only for the pleasure of Allah Ta’ala, but also to earn public praise.
Pearls Of Taqwa 