If one wants to analyze "Religio Laici", one has to consider the poem together with the preamble written by Dryden in the historical context. By itself the poem is an eloquent plea against institutionalized Christianity, giving the power of interpretation back to the individual and only leaving a few universal laws of Christian live in place. However, if considered in context, the poem is a strong voice against the Catholic influence in British affairs. Both in the preamble and the poem itself, Dryden references his strong support for the crown (the leader of the Anglican Church), while describing many features of the Catholic system as flawed.
Most of these points are used repetitively and are part of both the preamble and the poem, in differing prominence. The first that is mentioned here is the claim of Catholic scholars that any believe that is different from the Catholic system is wrong and will result in the person ending in hell. This is strongly contested by Dryden when he says that all people are only bound by the law of doing good in order to reach heaven, independent of their believe system. He goes as far as giving this to people that have lived before the Christian system, for example Greek Philosophers, and people that live outside the Christian realm, for example American Indians. Eternal damnation is one of the main arguments of any faith to keep their people in line. With this argumentation, Dryden very eloquently discharges this threat using Christian history and logic and therefore giving his readers the confidence in sticking to their believe system that is distinct from Rome. This lead to the second argument. Dryden vehemently disavows the infallibility of the papacy. Arguing that the papacy is just one of many interpretations of the word of God, he takes most of the power out of the pope's arguments. Considering that this happened in a time where religious figureheads had most of the power in the Western world, this argument is a strong support for the British crown, which fights against the papal influence.
Dryden's conclusion for the theological problem of who has the right to interpret the word and will of God is no one and everyone. He concedes that the word of God is ultimate and that no human mind can understand it, therefore taking away any power from all theological interpretations that have pretty much shaped the Catholic Church. At the same time he says that everyone should read the holy word and interpret it as they see fit, as long as they keep the basic rules given by God in their minds. This argument is very humanistic, as it gives agency to the simple layman and asks them to interpret beyond the translational errors. And while the poem itself gives very little support for the English throne as the leader of the Church, the historical context creates this support through the very explicit criticism of the Catholic system.