The line preceding this statement is
"Why Jericho? What does it mean? Biblically speaking?"
The implication is that by giving the child such an ostentatiously Christian name, they're making it all but certain that he'll end up taking holy orders and start wearing a clerical collar
The expression "a life of the collar" itself has been in common usage for some considerable time. For example;
Marcus Goulding, who is in his seventh year at the seminary and due to
be ordained a deacon on September 10, believes the church needs good
priests more than ever. Now aged 25, he got the marks to study law,
but the calling from God was louder. As he prepares for a life of the
collar rather than the wig, he feels a responsibility for restoring
the integrity of the church.
Daily Telegraph AU- Why young people are lining up to become priests and nuns