The image of the stunned and weary looking boy, sitting in an orange chair inside an ambulance covered in dust and with blood on his face, encapsulates the horrors inflicted on the conflict-hit northern city and is being widely shared on social media.
A doctor in Aleppo on Thursday identified the boy as five-year-old Omran Daqneesh.
Dr Osama Abu al-Ezz confirmed he was brought to the hospital known as "M10" on Wednesday night following an air strike on the rebel-held district of Qaterji with head wounds, but no brain injury, and was later discharged.
Doctors in Aleppo use code names for hospitals, which they say have been systematically targeted by government air strikes.
Rev Nadim Nassar said: "What more horrifying images will the world see from Syria before it acts?
"I'm speechless to see this child sitting looking shocked, confused, not knowing what's going on. Is that a message to the world? Yes it is.
"Have we seen more horrifying images? Yes we have and still the world has not reacted. Even the churches have not reacted. I don't know what will make the world react.
"We've lost our hearts, we've lost our feelings, we're numb to those images. We've reached a point that nothing moves us any longer."
In the video posted by the Aleppo Media Center, a man is seen plucking the boy away from a chaotic night time scene and carrying him inside the ambulance, looking dazed and flat-eyed.
The boy then runs his hand over his blood-covered face, looks at his hands and wipes them on the ambulance chair.
Opposition activists said there were eight casualties overall from the air strike on Qaterji, among them five children.
The image of Omran in the orange chair is reminiscent of the image of Aylan Kurdi, the drowned Syrian boy whose body was found on a beach in Turkey and came to encapsulate the horrific toll of Syria's civil war.
Rev Nassar added: "I can't imagine that any religious leader, any Christian leader, would see such an image and could sleep at night.
"Stand up, raise your voice and say enough is enough. Syria has lost more than a million people."
Gavin Crowden, World Vision UK's Head of Policy and Public Affairs said: "We are all heartbroken by the picture of five-year-old Omran. No boy, no child should ever need to be pulled from the rubble of an airstrike. But this is the grim reality of the Syrian crisis for its children.
"When we see Omran's picture it becomes so clear why families are forced to make treacherous journeys to seek safety for their children. Syria's children need a political solution to the crisis - now in its sixth bloody year.
"World Vision is calling for an immediate, weekly 48-hour ceasefire in the besieged city of Aleppo to enable children and their families to leave and let aid get to those left in the city."
Rev Nadim Nassar speaking to Premier's Antony Bushfield: