Question Summary:
Started Salah without wudhu and didn’t inform the congregation

Question Detail:

Assalamu alaykum 
I once led a salah in the mosque without wudhu, I started the salah without wudhu. This was around a few years ago and I didn't tell anyone because I was scared to embarrass myself. Now I realise what a huge sin I have done and I don't remember the people who prayed the salah behind me so now I am very worried as to what I should do. How do I get forgiveness for doing this. 

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
It is the responsibility of the Imam to ensure his Salah and the Salah of the congregation is performed meticulously without any deficiencies.
If for some reason the Salah was invalid, the Imam must inform the congregation.
In the enquired situation, you must inform whoever you remember from the congregation to repeat their Salah.[1]
If you are unable to recall the members of the congregation, make sincere tawbah, repent to Allah, and beg Him for forgiveness.  
If you are truly sincere in your repentance, Allah will forgive you inshaaAllah.
And Allah Ta’āla Knows Best
Saad Haque
Student Darul Iftaa
New Jersey, USA
Checked and Approved by,
Mufti Ebrahim Desai.