In The Name of Allaah, The Most Merciful, The Bestower of Mercy
The Messenger (sallal laahu alayhi wasallam) said: ”Indeed from the signs of the hour is that knowledge will be sought from the young ones.”
Ibn Mas’ood [radiyallaahu anhu] said: ”The people will not cease to be upon good as long as they acquire knowledge from their elders, their trustworthy ones and their scholars, for if they acquire it from their young ones and evil ones, they will be destroyed.”
Shaikh Abdus Salaam Burgess [rahimahullaah] stated in Awaa’iq At-Talab pages 29-35 that this ruling is not an absolute [or unrestricted] one against the young ones, for indeed there were a group of the Sahaabah and the Taabi’een who taught and gave verdicts in their young age, whilst the elders were present. However, the likes of these people are hard to find amongst those who came after them. So if they are found and are known for being upright, upon a sound [path] and they possess knowledge, and their firmness is manifested, whilst there are no elders to be found, then knowledge of the Sharee’ah is acquired from them – if they are free from fitnah! So the intent is not that the knowledge possessed by the young person is boycotted, whilst the elders are present; rather the intent is that the people are placed in their rightful positions.  The right [place] for the young one is that he is benefited from in studies, revision and research. As for issuing fatwa and questions sent to him [i.e. like the scholars are sent written questions to give fatwa], then no. Likewise, he does not enter into authorship. [Source: Awaa’iq At-Talab’ by Shaikh Abdus Salaam Burgess (rahimahullaah)…the above statement is an excerpt and a paraphrase, so refer to the Shaikh’s Risaalah on pages 29-34 for more benefits]
 NB: We return to the scholars to make known the positions and abilities of the students, whether they are young or old.