The Prophet ﷺ and his nation will stand witness for Nūḥ when his own nation will deny his mission
The Messenger of Allah ﷺ said, "Nūḥ and his nation will come ˹on Judgement Day˺ and Allah will ask, 'Did you convey ˹the Message˺?' He will reply, 'Yes, indeed O my Lord!' Then Allah will ask his nation, 'Did Nuḥ convey ˹the Message˺ to you?' They will reply, 'No, no prophet came to us.' Then Allah will ask Nūḥ, 'Who will stand a witness for you?' He will reply, 'Muhammad and his followers.' So, we will stand as witnesses for him." That is the Statement of Allah: "Thus we have made you a wasaṭ nation that you might be witnesses over mankind... (Baqarah 2:143)" and wasaṭ means justice.
قَالَ رَسُولُ اللَّهِ ﷺ: «يَجِيءُ نُوحٌ وَأُمَّتُهُ فَيَقُولُ اللَّهُ تَعَالَى: هَلْ بَلَّغْتَ؟ فَيَقُولُ: نَعَمْ أَىْ رَبِّ۔ فَيَقُولُ لأُمَّتِهِ: هَلْ بَلَّغَكُمْ؟ فَيَقُولُونَ: لاَ مَا جَاءَنَا مِنْ نَبِيٍّ۔ فَيَقُولُ لِنُوحٍ: مَنْ يَشْهَدُ لَكَ؟ فَيَقُولُ مُحَمَّدٌ ﷺ وَأُمَّتُهُ۔ فَنَشْهَدُ أَنَّهُ قَدْ بَلَّغَ۔» وَهْوَ قَوْلُهُ جَلَّ ذِكْرُهُ {وَكَذَلِكَ جَعَلْنَاكُمْ أُمَّةً وَسَطًا لِتَكُونُوا شُهَدَاءَ عَلَى النَّاسِ} وَالْوَسَطُ الْعَدْلُ۔»