It was narrated that ‘Ali (رضي الله عنه) said:

We saw the Messenger of Allah (ﷺ) standing so we stood, then we saw him remain seated so we remained seated (i.e., when a funeral passed by).

حَدَّثَنَا يَحْيَى، عَنْ شُعْبَةَ، حَدَّثَنَا مُحَمَّدُ بْنُ الْمُنْكَدِرِ، عَنْ مَسْعُودِ بْنِ الْحَكَمِ، عَنْ عَلِيٍّ، رَضِيَ اللَّهُ عَنْهُ قَالَ قَدْ رَأَيْنَا رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَامَ فَقُمْنَا وَقَعَدَ فَقَعَدْنَا‏.‏