Mahmood bin Labeeb R.A. narrates that Nabi Sallallahu Alaihi Wasallam said;

إنَّ أخْوَفَ ما أخافُ عليكم الشِّركُ الأصْغَرُ، قالوا: وما الشِّركُ الأصْغَرُ يا رسولَ اللهِ؟ قال: الرِّياءُ؛ يقولُ اللهُ عزَّ وجلَّ لهم يومَ القِيامةِ إذا جُزِيَ الناسُ بأعمالِهم: اذْهَبوا إلى الذين كنتُم تُراؤون في الدُّنيا، فانظُروا هل تَجِدون عِندَهُم جزاءً – أخرجه أحمد
‘I fear most for you the minor form of Shirk.”The Sahaba Radiyallah Anhu asked: “What is it?”. Nabi Sallallahu Alaihi Wasallam replied: “It is ostentation. On the day of Qiyamah, when people are rewarded for their actions, Almighty Allah will say to these people, “Go to those for whom you were showing off. See if they will give you anything.” Ahmed

1) A person is lazy to do good actions when no one sees them.
2)A person is eager to do good actions when people are watching.
3) A person excels in good actions when people praise him or her.
4) A person gives up doing a deed due to criticism.

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