Beware of Ar-Riya

Rasoolullahﷺ said, “What I fear for you the most is the minor shirk, that is ar-riya. Allah will say on the Day of Judgement when He is rewarding the people for their actions: Go to those for whom you did riya for in the world then see if you find the reward with them.”
[Related by Ahmad (5/428, 429) and al-Baghawi in Sharh as-Sunnah (4135) from the hadith of Mahmud bin Lubayd, radiallahu ‘anhu, with an authentic chain upon the conditions of Muslim]

Rasoolullahﷺ said, “Shall I not inform you of what I fear for you more than the Masih ad-Dajjal? It is the hidden shirk. It is when a man stands up for prayer, then beautifies his prayer for another to look at.”
[Related by Ibn Majah (2604) from the hadith of Abu Sa’id al-Khudri, radiallahu ‘anhu. The hadith is hasan]

Mahmud ibn Labid reported: Rasoolullahﷺ said, “Verily, my greater fear for you is the lesser idolatry.” They said, “What is the lesser idolatry, O Messenger of Allah?” The Prophet said, “It is ostentation. Allah Almighty will say to them on the Day of Resurrection, when people are being recompensed for their deeds: Go to those for whom you made a show in the world and look, do you find any reward with them?”
Source: Musnad Aḥmad 23630

Ibn ‘Abbas said: “Riyaa is more hidden than a black ant on a black stone in a dark night.”

Ma’qil ibn Yasar reported: I departed with Abu Bakr to meet Rasoolullahﷺ. And Rasoolullahﷺ said, “O Abu Bakr, there is idolatry among you more hidden than the crawling of an ant.” Abu Bakr said, “Is there idolatry other than to make another god alongside Allah?” Rasoolullahﷺ said, “By one in whose hand is my soul, there is idolatry more hidden than the crawling of an ant. Shall I not tell you something to say to rid you of it both minor and major? Say: O Allah, I seek refuge in you that I associate partners with you while I know, and I seek your forgiveness for what I do not know.”

Source: al-Adab al-Mufrad 715
Grade: Sahih

عن معقل بن يسار قَالَ انْطَلَقْتُ مَعَ أَبِي بَكْرٍ الصِّدِّيقِ رَضِيَ اللَّهُ عَنْهُ إِلَى النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ يَا أَبَا بَكْرٍ لَلشِّرْكُ فِيكُمْ أَخْفَى مِنْ دَبِيبِ النَّمْلِ فَقَالَ أَبُو بَكْرٍ وَهَلِ الشِّرْكُ إِلا مَنْ جَعَلَ مَعَ اللَّهِ إِلَهًا آخَرَ فَقَالَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَالَّذِي نَفْسِي بِيَدِهِ لَلشِّرْكُ أَخْفَى مِنْ دَبِيبِ النَّمْلِ أَلا أَدُلُّكَ عَلَى شَيْءٍ إِذَا قُلْتَهُ ذَهَبَ عَنْكَ قَلِيلُهُ وَكَثِيرُهُ قَالَ قُلِ اللَّهُمَّ إِنِّي أَعُوذُ بِكَ أَنْ أُشْرِكَ بِكَ وَأَنَا أَعْلَمُ وَأَسْتَغْفِرُكَ لِمَا لا أَعْلَمُ

On the authority of Abu Hurayrah (R), who said:
I heard Rasoolullahﷺ say: The first of people against whom judgment will be pronounced on the Day of Resurrection will be a man who died a martyr. He will be brought and Allah will make known to him His favours and he will recognize them. [ The Almighty] will say: And what did you do about them? He will say: I fought for you until I died a martyr. He will say: You have lied – you did but fight that it might be said [of you]: He is courageous. And so it was said. Then he will be ordered to be dragged along on his face until he is cast into Hell-fire. [Another] will be a man who has studied [religious] knowledge and has taught it and who used to recite the Quran. He will be brought and Allah will make known to him His favours and he will recognize them. [The Almighty] will say: And what did you do about them? He will say: I studied [religious] knowledge and I taught it and I recited the Quran for Your sake. He will say: You have lied – you did but study [religious] knowledge that it might be said [of you]: He is learned. And you recited the Quran that it might be said [of you]: He is a reciter. And so it was said. Then he will be ordered to be dragged along on his face until he is cast into Hell-fire. [Another] will be a man whom Allah had made rich and to whom He had given all kinds of wealth. He will be brought and Allah will make known to him His favours and he will recognize them. [The Almighty] will say: And what did you do about them? He will say: I left no path [untrodden] in which You like money to be spent without spending in it for Your sake. He will say: You have lied – you did but do so that it might be said [of you]: He is open-handed. And so it was said. Then he will be ordered to be dragged along on his face until he is cast into Hell-fire. It was related by Muslim (also by at-Tirmidhi and an-Nasa’i).