It is because of their potency in generating obligations that oaths are at the heart of the constitution of political communities. The oath is one of those concepts that have undergone numerous theological– political transfers, to which Carl Schmitt referred when talking about political theology. Schmitt himself thought that the oath will always remain a necessary institution, no matter how much it might seem to have disappeared from public life: whatever the formula, it ensures internal disposition, so that the institutions of the modern state are not abused and their very foundations destroyed. In fact, when written constitutions emerge, legislatures seek to institute and sanction their identity through solemn declarations, for example, by appealing to God or some other moral or ideological formula. Paolo Prodi, following Schmitt's theological–political hypothesis, declares that the oath is the basis of the political covenant in Western societies. Prodi's main theological–political argument is that the modern state has taken the place of God as the absolute witness of every oath as a result of the secularisation process. Hence, the oath has become a prerogative of sovereignty.

The oath, as a mutual promise between two or more persons to trust each other's word under the sight of the ‘immortal God’, can be understood as a meta-political guarantor of the political bond. Consequently, it is possible to think as Prodi does, that the decline of the oath to the status of a solely secular commitment, which can be broken at any time, carries with it the crisis of the very idea of political community. In contrast to this catastrophist thesis, Aroney still perceives that oaths of office and oaths of allegiance have marked the path of the authority of the modern state and continue to do so until today. In fact, he argues, that we can still find the theological–political paradox at the core of the state's institutional proceedings and arrangements. On the one hand, oaths seek to guarantee the performance of official duties; on the other hand, they subject the content of those duties to another potestas external to that of the state, that of God.