The defendant may waive his constitutional right to a fair and impartial jury, and accept a juror who is prejudiced or has expressed an opinion, if he desires, and the court cannot, on its own motion, reject such juror and refuse to permit him to be sworn as one of the jurors to try the cause.41

The twelve jurors having been selected, they shall be sworn as prescribed by statute. The substance of the oath cannot be dispensed with.42 The statutory form of the oath is, in substance, the same as that of the common law, with modifications to suit our form of government.