The Oklahoma man FBI agents arrested last month for allegedly throwing a pipe bomb onto the porch of Salem’s The Satanic Temple has been indicted on federal charges.

“Dear Satanist, Elohim send me 7 months ago to give you peaceful message to hope you repent. You say no, Elohim now send me to smite Satan and I happy to obey,” began a six-page, handwritten letter the feds allege Sean Patrick Palmer stuck in a The Satanic Temple flower bed near where he is said to have thrown a pipe bomb in the early morning of April 8.

“Elohim send me to fight crybaby Satan, but want me to make hard effort so no one dies,” Palmer allegedly continued. “I obey.”

Palmer, 49, of Perkins, Okla., was charged by criminal complaint and arrested on April 17 in his hometown. On Friday, a federal grand jury in Boston indicted him on one count of using fire and an explosive to damage and attempt to damage a building used in interstate or foreign commerce. The charge carries a minimum of five years and up to 20 years in prison, if Palmer is convicted.

The feds say that a man they believe to be Palmer approached the Temple at about 4:14 a.m. on April 8 wearing a black face covering, a tan-colored tactical vest and gloves and proceeded to light up a pipe bomb and throw it on the building’s front porch. The bomb was made from plastic pipe stuffed with smokeless gunpowder and covered in metal nails, the feds say.