 Although he was ostracized for his political beliefs, leading literary figures continued to meet with him and admired his work, among them Avot Yeshurun.One of Penn's most well-known poems was "Vidui" (My Confession), a turbulent piece about love and death.The poem was set to music in the early 1970s and has been recorded since then by numerous Israeli singers and musicians, including Michal Tal, Yehudit Ravitz and more recently, Marina Maximilian Blumin.