Before Abu Sufyan was a Muslim he was the leader of the non muslim army in Makkah. They had sent a huge army to attack the Prophet (pbuh). The army of Muslims at that time was just 313 people. They didn’t even have arms to protect themselves.
They were told Abu Sufyan and his army were coming. The Prophet and the true believers became firm in their faith and said “Allah is sufficient for us and is the best disposer of our affairs”.
When Allah keeps closing doors you have to be convinced that the help of Allah is coming. If you give up that is when hope stops. A believer does not give up hope.