He is an advocate for a revolutionary government in the Philippines[2] Tayag co-founded, along with Jose Maria Sison and others, the Maoist youth group Kabataang Makabayan ("Patriotic Youth") in 1964, which became the nucleus of the established Communist Party of the Philippines in 1968, and served as its Central Committee member.
[4] He was the group's national chairman until he was arrested on June 11, 1970 in Barrio Concepcion, San Pablo, Laguna.
[3] Detained along with Benito Tiamzon, Jesus Lava and other left-wing personalities at the Youth Rehabilitation Center in Fort Bonifacio, and later declaring support for the incumbent president Ferdinand Marcos, he was released in 1981 or 1982 after pleading guilty to the charge of subversion.
[5] After being released from prison, Tayag undertook theology studies in the Iglesia Catolica Filipina Independiente (ICFI) National Seminary at Batac, Ilocos Norte (a splinter group from the Philippine Independent Church).
[2] He was a prominent supporter of Rodrigo Duterte during the latter's campaign for the Presidency[8] and is a founding member of the "Democratic Front for Filipinism" and "Kilusang Pilipinismo", groups supporting Duterte's "revolution against illegal drugs, the oligarchs and the exploiters of the Filipino masses.