Merseyside Police released an image of a man they wish to speak to following the alleged incident on December 6, at around 11am.
Officers said the teenager had suffered a minor injury after being kicked during the attack.
A number of lines of enquiry are being pursued, police said.
Detective Constable Joanne Brough, of the specialist Sigma Hate Crime team, said: "We are treating this as a racially aggravated assault and specialist officers from the force's Sigma team are conducting enquiries.
"The victim, thankfully, only suffered a minor injury but has been left very distressed following this incident.
"I am sure the local community would agree that this type of behaviour is not acceptable, especially in a place of worship and has no place on Merseyside. I would, therefore, ask anyone who has any information about this incident or who recognises this man to get in contact."
Anyone with information is asked to call the Liverpool Sigma team on 0151 777 4048 or Crimestoppers anonymously on 0800 555 111.