According to another version of this Hadith, Rasulullah (sallallahu ‘alaihi wasallam) was calling the people saying:
يا أيها الناس إن الله يأمركم أن تعبدوه ولا تشركوا به شيئا
O people! Allah commands you to worship Him and to abstain from ascribing any partner unto him!
While Rasulullah (sallallahu ‘alaihi wasallam) was inviting the people towards Islam, Abu Lahab walked behind him calling out:
يا أيها الناس إن هذا يأمركم أن تتركوا دين آبائكم
O people! This man is commanding you to renounce the religion of your forefathers! Do not listen to him!
The pinnacle of Allah’s creation, Rasulullah (sallallahu ‘alaihi wasallam), was inviting people towards Islam and Daar-us-Salaam (Jannah) while Abu Lahab was calling people towards نارا ذات لهب (the blazing fire of Jahannum).
(Extracted from Seeratul Mustafaa 1/179)