From here:

The Advertising Standards Authority (ASA) said it had concluded that the adverts by Healing on the Streets (HOTS) – Bath, were misleading.

It said a leaflet available to download from the group’s website said: “Need Healing? God can heal today!”

[….]

The ASA said it had been alerted to the adverts by a complainant, and concluded that they could encourage false hope and were irresponsible.

If all advertising that “could encourage false hope” were banned, then there would be very little advertising at all and the economy of the UK would collapse even faster than it already is.

The fact that these advertisements have been singled out for special opprobrium is yet another example of secularism’s attempt to expunge Christianity from public view.

On purely factual grounds the ban is absurd: if a person believes there is no God, his hopes for healing will not be stimulated by the ad; if a person believes in God, but he doesn’t actually exist, he is already so deluded that one more false hope won’t make much difference; if a person believes in God and God does exist, then there is no false hope in believing God can heal – he can do anything he chooses, including heal.