A top US web designer has hit out at sites that substitute style for substance, singling out US churches and high schools as the world's worst offenders.

He has set up a site called HealYourChurchWebsite.com in an effort to advise churches how to avoid the worst web-design sins.

Peters, who penned a chapter in the design bible Son of Web Pages That Suck by Vincent Flanders, believes the internet should be able to handle the depths of spiritual messages.

But pastors and volunteers manage to mangle their message through "a great cloud of witlessness" while, in the case of high schools, "impatience and impetuousness usually lead to web designs that are... well... only suited for churches!" he said.

"The internet is a tool and when it is handled properly, it can be used to make effective and attractive websites," he said.

But the immediacy of the web made it too easy for Church and para-Church organisations to lose focus, he warned.

"If the web designer isn't much of a deep thinker, then we shouldn't expect websites of any great depth," he said.

Peters criticised church site designers who took the shortest routes to creating the visual content of their sites, such as substituting things tacky for things technical.

Spinning crosses and flapping angels are all typical of tacky material that seem like a good idea for such sites.

Church websites needed healing because their webmasters jumped right in without giving any thought or prayer to their efforts. "Because they do not think through their content, the site appears disorganised and is often difficult to navigate," Peters said.

And with so many Christians exchanging style over substance in modern life, the Church was losing its ability to influence culture, Peters said. "Instead [it] is now wretchedly under the influence of rampant post-modernism. This is especially evident here in the States, even more so on the web.

"Many in the Church have forgotten, or never been taught, that they are not only to love God with all their heart and soul, but also their MINDS," he added.

"I teach 11th grade Sunday school. Yet few students know who Constantine was, let alone the persecution of the early Church. They'll gladly spend five hours watching the TV a day, but moan and groan when I ask them to read five minutes of scripture weekly."