1. In a penitent manner.

2. With penitence.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• penitentery,
• paitently,
• penitentary,
• persitently,
• penitentury,
• pesistently,
• patitently,
• penitentally,
• oenitently,
• lenitently,
• -enitently,
• 0enitently,
• pwnitently,
• pentently,
• punitently,
• penitantly,
• Oscitently,
• Pendentley,
• Penentently,
• Penitencely

• pendent,
• penitential,
• penitentially,
• penitent,
• penitence,
• penitentiary.

The adjective form of "penitently" is "penitent".