The Imam of our local mosque has made a system to deliver short speeches on various islamic topics say for 5-10 minutes before starting the maghrib salat in jamat almost everyday. Is it ok according to sunnah or is it Bidah?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

What the Imaam you referred to does is disliked in our view for two reasons:

1- Continuously preaching every day will probably make the people lose interest. Shaqeeq abi Waa'il narrated: ‘Abdullaah used to give a sermon every Thursday. Once a man said, “O Abu ‘Abdur-Rahmaan! We like your talk and we look forward to it, and we wish that you would preach to us every day.” He replied, “The only thing which prevents me from doing so is that I fear to bore you, as the Prophet used to preach to us by selecting a suitable time to do so, for fear of making us bored.” [Al-Bukhari and Muslim]

Ibn Hajar said: “Al-Khattaabi said: the meaning is that he [the Prophet] used to choose the appropriate times to teach them and preach them and he did not do so every day for fear of causing boredom to the people...” [Fat-h Al-Baari]

Ibn ‘Abbaas said: “Preach to the people once a week (from Friday to Friday), or twice, and if you wish to preach to them much, then let it be three times as you should not bore the people of this Quran.” [Al-Bukhari]

Moreover, Sharh As-Sunnah of Imaam Al-Baghawi reads: “‘Aa’ishah said to ‘Ubayd ibn ‘Umayr: “Did I not tell you that you sit (to preach to the people) and people sit to listen to you?” He said: “Yes, O Mother of the Believers.” She said: “Beware of causing boredom to people and of making them despair.” It was also reported that she said to him: “Preach every other day so as not to make the people bored.”

The Fiqh Encyclopedia reads: “The scholars are of the view that it is desirable to preach to people from time to time while choosing the appropriate times to preach to them, and choosing the best times when it is most likely that they would listen, but one should not preach every day so as not to make them bored of listening to the admonition. What should be taken into account is the need and the times when the people are willing to listen, because if there are so many sermons, they do not affect the hearts and there would be no benefit of the sermons in this case due to their frequency.”

2- Preaching [at this time] may lead to delaying the Maghrib prayer from the beginning of its time; the jurists unanimously agreed that it is desirable to perform the Maghrib prayer at its beginning time on account of the Ahaadeeth in this regard, such as the Hadeeth of Salamah ibn Al-Akwa’ who said: “The Prophet used to pray the Maghrib prayer when the eyebrow of the sun (i.e. the upper part of it which looks like an eyebrow when it sets) disappears.” [Abu Daawood]

And the Hadeeth by Abu Mahthoorah who said: “The Prophet said to me: “If you call the Athaan for the Maghrib prayer, then hasten to perform it as soon as the sun sets.”

The Fiqh Encyclopedia reads: “As regards the desirable time for the Maghrib prayer, then we are not aware of any disagreement among the scholars that it is desirable to hasten to perform it.”

As regards determining a certain hour for the lesson or sermon, like after the prayer, for example, in a way that it is repeated on a regular basis in order to teach knowledge to the people, then this is not considered an innovation because it is not intended as an act of worship in learning knowledge at this particular time, but what is intended is to learn knowledge regardless of the time. Indeed, Imaam Al-Bukhari entitled a chapter: "Chapter of whoever allocates particular days for the learned", and he cited in this Chapter the Hadeeth of Abu Waa'il, which we mentioned earlier. However, it is admonishing people too much that the preacher should avoid.

Allaah Knows best.