Rat poison is the latest church trend. Well, it is if you are a stunt-pastor in South Africa.

After the cheap thrills of the "prophet of doom" spraying churchgoers with pesticide and others forcing congregants to drink the antiseptic cleaning product Dettol and engine cleaning fluid, the latest "miracle prophet" has turned to rat poison.

Pastor Light Monyeki, of Grace Living Hope ministry, has been pictured mixing Rattex with water and offering it to drink for "nourishment and healing".

Monyeki is among a new generation of pastors looking to prove God's power, and their own anointing, by parading their miraculous prowess.

But they are not just proving a worry for health and government officials concerned about the congregations being poisoned.

They twist and misunderstand the Bible to such an extent they are a headache for anyone trying to teach genuine Christianity.

In a revealing interview Monyeki said he was doing the stunt to prove the power of God.

"When we pray over anything, its poison dies. So it can't harm people. Nothing happened, no one has been to hospital," he said.

But he bases his main rationale on a couple of verses in Mark's Gospel:

Mark 16: 17-18 says: "In my name shall they cast out devils; they shall speak with new tongues. They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover."

This is worryingly misguided.

Firstly that section of Mark 16, verses 9-20, is not in the earliest and most reliable manuscripts we have and other ancient witnesses also don't have them. That is not to say we should ignore them.

But it is highly likely they were added years later by another source other than the author of Mark.

And so it is not wise to base any belief, especially not one as extreme as this, on these bonus verses.

Beyond that the idea of testing God to demonstrate your own power directly contradicts other parts of the Bible.

When he was tempted in the desert Jesus was taken to the highest point of the temple. "If you are the son of God," the devil says, "throw yourself down from here."

Much like the South African pastor, Satan then quotes one verse out of context.

"For it is written," he says, "'He will command his angels concerning you to guard you carefully; they will lift you up in their hands, so that you will not strike your foot against a stone.'"

But Jesus' answer is telling. And it provides the main problem with the South African pastor's approach.

"Jesus answered, 'It is said: 'Do not put the Lord your God to the test.'".

By feeding their congregations rat poison the pastors are doing nothing other than putting God to the test.

There are plenty of examples of good people being given extraordinary powers in the Bible. The disciples healed the sick. And Paul handled a snake safely in Acts 28:5.

Those are particular examples of God intervening by his power. But it does not involve testing God in order to show off your own power. It does not mean trying to tempt the laws of nature or putting ourselves in danger for the sake of it or to prove a point.

Christians base their witness on Jesus, not on supernatural stunts.

And the South African pastors come down the wrong side of that fence in this case.