Shaykh Ibn ‘Uthaymeen said:
And amongst them was ‘Umar ibn Abee Salamah (radhi-yAllaahu ‘anhu), and he was small, a young boy.
He sat with the Messenger (sal-Allaahu ’alayhi wa sallam) to eat, and his hand started to wander around the plate.
He was a young boy, small, and had not learnt [the correct manners when eating]; his hand wandering right and left.
He ate from what was in front of him, and from the middle of the plate and from the other side [too].
So the Prophet (sal-Allaahu ’alayhi wa sallam) said to him:
«O young boy utter the name of Allaah…», meaning, say “bismillaah” when eating.
«…and eat with your right hand, and eat from what is nearest to you.»
How the Messenger (sal-Allaahu ’alayhi wa sallam) taught this young boy three [acts of the] Sunnah!
«…utter the name of Allaah…» – and to utter “bismillaah” when eating is obligatory.
«…and eat with your right hand…» – and eating with the right hand is obligatory.
«…and eat from what is nearest to you» – being civil to your [eating] companion.
Because it is from bad manners to eat from the side of your [eating] companion.
«…eat from what is nearest to you»
So the Prophet (sal-Allaahu ’alayhi wa sallam) taught him three [acts of the] Sunnah during one meal, and this [really] is from the blessings of the Prophet (sal-Allaahu ’alayhi wa sallam) that Allaah has rendered in him blessings, that he teaches in any situation [he may be in].
And likewise it is befitting for the student of knowledge, and other than the student of knowledge – everyone who knows a[n act of the] Sunnah [of the Prophet (sal-Allaahu ’alayhi wa sallam)] – then it is befitting that they explain it [to the people] in any gathering.
And don’t say “I am not a scholar.” Yes, you are not a scholar, but you have [some] knowledge.
[Remember], the Prophet (sal-Allaahu ’alayhi wa sallam) said:
«Convey from me, even a [single] verse» – so it is befitting for a person in the likes of these situations that he seize the opportunities.
Whenever the opportunity permits you to spread [knowledge of] the Sunnah, then spread it; [in doing so] there will be for you reward and the reward for everyone who acts upon it until the day of resurrection.
And Allaah is the Expounder of all success.