It was narrated from Salim that his father said: "I saw the Prophet ﷺ, Abu Bakr and 'Umar walking ahead of the funeral (procession)".
The hadith also teaches us about humility; even though these three men were some of the most important people in Islamic history, they still chose to walk at the front of a funeral procession instead of riding or being carried on a horse or camel like many other people would do at that time. This shows us that no matter how important we are, we should always be humble and remember our place before Allah SWT.