Reviews were favourable for each poem. The completed set received divided reviews in the United States while it was received overall favourably by the British. The American critics liked the poetry but many did not appreciate the religious content of the work or that Eliot abandoned philosophical aspects of his earlier poetry. The British response was connected to Eliot's nationalistic spirit, and the work was received as a series of poems intended to help the nation during difficult times. Santwana Haldar went so far as to assert that the "Four Quartets has been universally appreciated as the crown of Eliot's achievement in religious poetry, one that appeals to all including those who do not share Orthodox Christian creed."
George Orwell believed just the opposite. He argued: "It is clear that something has departed, some kind of current has been switched off, the later verse does not contain the earlier, even if it is claimed as an improvement upon it [...] He does not really feel his faith, but merely assents to it for complex reasons. It does not in itself give him any fresh literary impulse." Years later, Russell Kirk wrote, "I cannot agree with Orwell that Eliot gave no more than a melancholy assent to doctrines now quite unbelievable. Over the past quarter of a century, most serious critics—whether or not they find Christian faith impossible—have found in the Quartets the greatest twentieth-century achievements in the poetry of philosophy and religion." Like Orwell, Stead also noticed a difference between the Four Quartets and Eliot's earlier poetry, but he disagreed with Orwell's conclusion: "Four Quartets is an attempt to bring into a more exact balance the will and the creative imagination; it attempts to harness the creative imagination which in all Eliot's earlier poetry ran its own course, edited but not consciously directed. The achievement is of a high order, but the best qualities of Four Quartets are inevitably different from those of The Waste Land.
Early American reviewers were divided on discussing the theological aspects of the Four Quartets. F. R. Leavis, in Scrutiny (Summer 1942), analysed the first three poems and discussed how the verse "makes its explorations into the concrete realities of experience below the conceptual currency" instead of their Christian themes. Muriel Bradbrook, in Theology (March 1943), did the opposite of F. R. Leavis and emphasised how Eliot captured Christian experience in general and how it relates to literature. D. W. Harding, in the Spring 1943 issue of Scrutiny discussed the Pentecostal image but would not discuss how it would relate to Eliot's Christianity. Although he appreciated Eliot's work, Paul Goodman believed that the despair found within the poem meant that Eliot could not be a Christian poet. John Fletcher felt that Eliot's understanding of salvation could not help the real world whereas Louis Untermeyer believed that not everyone would understand the poems.
Many critics have emphasised the importance of the religious themes in the poem. Vincent Bucklet stated that the Four Quartets "presuppose certain values as necessary for their very structure as poems yet devote that structure to questioning their meaning and relevance. The whole work is, in fact, the most authentic example I know in modern poetry of a satisfying religio-poetic meditation. We sense throughout it is not merely a building-up of an intricate poetic form on the foundation of experiences already over and done with, but a constant energy, an ever-present activity, of thinking and feeling." In his analysis of approaches regarding apocalypse and religious in British poetry, M H Abrams claimed, "Even after a quarter-century, T. S. Eliot's Four Quartets has not lost its status as a strikingly 'modern' poem; its evolving meditations, however, merely play complex variations upon the design and motifs of Romantic representation of the poets educational progress."
Late 20th century and early 21st century critics continued the religious emphasis. Craig Raine pointed out: "Undeniably, Four Quartets has its faults—for instance, the elementary tautology of 'anxious worried women' in section I of The Dry Salvages. But the passages documenting in undeniable detail 'the moment in and out of time' are the most successful attempts at the mystical in poetry since Wordsworth's spots of time in The Prelude—themselves a refiguration of the mystical." Michael Bell argued for the universality within the poems religious dimension and claimed that the poems "were genuinely of their time in that, while speaking of religious faith, they did not assume it in the reader." John Cooper, in regard to the poem's place within the historical context of World War II, described the aspects of the series appeal: "Four Quartets spoke about the spirit in the midst of this new crisis and, not surprisingly, there were many readers who would not only allow the poem to carry them with it, but who also hungered for it."
In a more secular appreciation, one of Eliot's biographers, the critic Peter Ackroyd, has stated that "the most striking characteristic of The Four Quartets is the way in which these sequences are very carefully structured. They echo and re-echo each other, and one sequence in each poem, as it were, echoes its companion sequence in the next poem. . . The Four Quartets are poems about a nation and about a culture which is very severely under threat, and in a sense, you could describe The Four Quartets as a poem of memory, but not the memory of one individual but the memory of a whole civilization."