Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:4:151 –

Those are the disbelievers, truly. And We have prepared for the disbelievers a humiliating punishment.  

Those are the disbelievers truly (haqqan is the verbal noun, emphasising the content of what precedes it in the sentence); and We have prepared for the disbelievers a humiliating chastisement, namely, the chastisement of the Fire.
القرآن:٤:١٥١ –

أُولَٰئِكَ هُمُ الْكَافِرُونَ حَقًّا ۚ وَأَعْتَدْنَا لِلْكَافِرِينَ عَذَابًا مُهِينًا  

{أولئك هم الكافرون حقا} مصدر مؤكد لمضمون الجملة قبله {وأعتدنا للكافرين عذابا مهينا} ذا إهانة وهو عذاب النار.