An 80-year-old man believed he was following the Bible when he used an alkathene pipe to punish a child for stealing $1000 from him.

The man, who has interim named suppression, yesterday pleaded guilty in the New Plymouth District Court to two charges of assaulting a child and assault with a blunt instrument between November 1 and December 7.

When arrested, the man told police that he was frustrated by the child's behaviour and had been "seeking to correct him in the manner described in the Bible".

His lawyer, Paul Keegan, said the incident was out of character for the man.

"He is a Christian man and believes firmly in traditional methods of discipline," he said.

Judge David Ongley said there was a firm belief in the community that there should be no unnecessary force used to discipline children, that it was not acceptable and required a penalty.

The defendant was allowed interim name suppression until sentencing on February 12.