Question Summary:
What is the ruling regarding announcements/advices offered by the Imam after the fardh prayer and before the sunnah?

Question Detail:

I have a query with regards to the different activities that take place between the Fardh and Nawafil prayers in the masajid:
1)     The reading of sunnah and etiquettes for a very short time.
2)     In some places, the Imam stands facing the congregation and advises them for two-three minutes.
3)     Many masajid make announcements with regards to making dua for the sick.  Likewise, announcements are made with regards to janazah salaah.
4)     In some madaris, a student recites one page of the Quran as a means of encouragement.
What is the ruling with regards to these acts? These activities take place whilst those who have missed a rakat are usually performing their salaah.  At times people start their nawafil and the Imam starts speaking on the microphone.  

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful. 
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
 

In a congregational act, every individual should consider the other.  In salāh and after salāh, the Imām genuinely has the best interests of the followers at mind.  Likewise, the followers exhibit their consideration by sitting and listening to what the Imām has to say.  The public genuinely do come to the masjid for salāh and to be educated in matters of Dīn.  In addition, the time after salāh where everybody is gathered is a golden opportunity to educate the masses.
Thus, it is permissible to narrate a few masā’il or etiquettes after the fardh salāh.  The importance of educating the mass public cannot be over emphasised.[1]  At the same time, it is important to take into consideration the late comers to salāh.[2]  In addition, it is makrūh to lengthen the time between the fardh and sunnah.[3]  Thus, the Imam should keep the advice/announcement as short as possible and in an adequate volume which is loud enough for the congregation to hear and does not overpower the latecomers’ concentration.[4]  An advice approximately one minute seems to appropriate.     
With regards to the Imam giving nasīhah for 2-3 minutes, if this is done daily and the people who perform salāh there are comfortable with it, then it will be alright to carry on with it. 
There is nothing wrong with making announcements after the salāh which are not related to worldly affairs like transactions etc.[5] 
With regards to making a child recite the Qur῾ān after salāh, it is a praiseworthy act for encouragement.  However, if the masjid/musallā is frequented by the mass public, then this can be a hindrance for them.  Another mechanism may be considered to encourage the students.   
And Allah Ta’āla Knows Best
Mawlana Faraz ibn Adam,
Student Darul Iftaa
Leicester, United Kingdom
Checked and Approved by,
Mufti Ebrahim Desai.
www.daruliftaa.net