By Tony Hanson

PHILADELPHIA (CBS) — It was attack and counterattack today in a Philadelphia courtroom, as another case of alleged clergy sexual abuse in the Archdiocese of Philadelphia begins (see related stories).

Father Charles Engelhardt and former lay teacher Bernard Shero are charged with sexually abusing the same boy during the 1998 and 1999 school years (see related story).

Today, during opening statements, prosecutor Evangelia Manos told the jury that “evil lurks disguised in sheep’s clothing” — in this case a priest’s collar or the clothing of a teacher.

According to Manos, Engelhardt and Shero abused the boy, ultimately damaging his mind, his body, and his soul.

And Manos today revealed that a third person, a priest who admitted sexually abusing the same boy (see related story), will also be called to testify.

But both defendants have pleaded not guilty before the jury.

Michael McGovern, Father Engelhardt’s attorney, says there will be a mountain of reasonable doubt, adding that his client, a good man, is being destroyed by falsehoods.

The defense has suggested that drugs ruined the alleged victim’s life, and that the man is now motivated by money that may come from a lawsuit against the defendants and the archdiocese.

The prosecutor revealed during her opening statement that Shero made a suicide attempt after the allegations against him came to light.