Fundamental theology is a branch of Catholic theology which seeks to establish the fact that God has made a supernatural revelation and established the Catholic Church as its divinely authorized custodian and interpreter. Fundamental theology is a branch of Catholic theology which seeks to establish the fact that God has made a supernatural revelation and established the Catholic Church as its divinely authorized custodian and interpreter. Unlike apologetics, fundamental theology does not directly work towards evangelization, but rather towards the analysis of where and by what means God brings human beings to assent to his Word.