In 1984, Petersen married Zina Nibley, a daughter of Hugh Nibley. They have four children and reside in Provo, Utah. Petersen has been a lecturer in the honors program at BYU, and for the English and Humanities Departments at Utah Valley University, where he received a Faculty Excellence Award in 2006. Through his familial relationship to Hugh Nibley, Petersen authored the 2002 biography Hugh Nibley:
Hugh Nibley
Petersen