Is it permissible to give a lecture at a funeral?

Answer

If by 'funeral' you mean that a lecture is given while the dafan (burial) of the mayyit (deceased) is delayed, then it will be haraam to indulge in a lecture. It is not permissible to delay the burial with a lecture or any other unnecessary activity. Rasulullah (sallallahu alayhi wasallam) emphasized haste in the burial.