Rasulullah (sallallahu ‘alaihi wasallam) was once seated with Hazrat Abu Bakr (radhiyallahu ‘anhu), Hazrat Umar (radhiyallahu ‘anhu), Hazrat Abu Ubaidah (radhiyallahu ‘anhu) and other Sahaabah (radhiyallahu ‘anhum) when a drink was presented to Nabi (sallallahu ‘alaihi wasallam).
Nabi (sallallahu ‘alaihi wasallam) took the drink in his hand and offered it to Hazrat Abu Ubaidah (radhiyallahu ‘anhu) to drink first. However, Hazrat Abu Ubaidah (radhiyallahu ‘anhu), out of respect for Rasulullah (sallallahu ‘alaihi wasallam), did not wish to drink first and said to Rasulullah (sallallahu ‘alaihi wasallam), “O Nabi of Allah! You are more deserving to drink first.”
Nabi (sallallahu ‘alaihi wasallam) then said to him, “Abu Ubaidah, you drink (first).” Hazrat Abu Ubaidah (radhiyallahu ‘anhu) then accepted the utensil from Nabi (sallallahu ‘alaihi wasallam).
Nevertheless, before drinking, he once again, out of honour, love and respect for Rasulullah (sallallahu ‘alaihi wasallam), said to Nabi (sallallahu ‘alaihi wasallam), “O Nabi of Allah! You take it (and drink first).” Nabi (sallallahu ‘alaihi wasallam) addressed him saying:
اشرب فإن البركة مع أكابرنا
“(O Abu Ubaidah!) You drink (first), as barakah (blessings) lies with our elders (i.e the ummah will receive barakah from Allah Ta’ala by them showing respect to their elders and allowing them to do things first).”
Rasulullah (sallallahu ‘alaihi wasallam) thereafter mentioned:
فمن لم يرحم صغيرنا ويجل كبيرنا فليس منا
“The person who does not show mercy to the young among us and does not respect the seniors among us, then he is not from among us (i.e. he is not following our path – the path of the sunnah).”
(Majma’uz Zawaaid #8264)
N.B. It should be borne in mind that when interacting with one’s seniors, the sunnah is that one show love and respect to them. The sign of showing love and respect to them is that one gives preference to them over oneself.
It is for this reason that when Rasulullah (sallallahu ‘alaihi wasallam) – the imam of all the Ambiya and Rasuls – presented the drink to Hazrat Abu Ubaidah (radhiyallahu ‘anhu) to drink first, he did not want to drink first, but twice requested Rasulullah (sallallahu ‘alaihi wasallam) to drink before him, as Rasulullah (sallallahu ‘alaihi wasallam) is the most worthy person to drink first.
However, when Rasulullah (sallallahu alaihi wasallam) commanded him to drink first, then he immediately submitted, as obeying the command of Rasulullah (sallallahu ‘alaihi wasallam) (or one’s senior) will be given preference over one’s desire of wanting to show respect to them, and this will be conforming to the sunnah in this situation.
From this incident, we see that Rasulullah (sallallahu ‘alaihi wasallam) wished to show the ummah the high, esteemed position of Hazrat Abu Ubaidah (radhiyallahu ‘anhu) so that they also respect him accordingly.
One way for Rasulullah (sallallahu ‘alaihi wasallam) to show the Sahaabah (and the ummah) the esteemed position of Hazrat Abu Ubaidah (radhiyallahu ‘anhu) was to verbally explain to them his virtue. This Rasulullah (sallalllahu ‘alaihi wasallam) had done by mentioning to the ummah that Hazrat Abu Ubaidah (rdhiyallahu ‘anhu) is the special trustee of this ummah.
The second way for Rasulullah (sallallahu ‘alaihi wasallam) to show the Sahaabah (and the ummah) the esteemed position of Hazrat Abu Ubaidah (radhiyallahu ‘anhu) was to practically demonstrate before them an action through which they will understand his honour and respect and thereby also show him honour and respect. Therefore, Rasullullah (sallallahu ‘alaihi wasallam) requested him to drink first – to show the ummah his esteemed position and honour.