張秀亞一生所寫的詩共計約二百一十三首，大部份分別載入於《水上琴聲》、《秋池畔》、《我的水墨小品》、《愛的又一日》之中，其餘未編輯成冊或創作年代不明的詩，直至國家台灣文學館出版《張秀亞全集》，才將其收入於第一集－詩卷，而成為這本詩集的第五部份「未集結詩」。在這二百一十三首詩中，有關宗教的詩作大約有三十五首左右（純粹的宗教詩約十五首），雖然所佔的篇幅並不多，但對其生命、精神、思想與創作的重要性卻是無庸置疑的。眾所周之，張秀亞是個虔誠的天主教徒，對上帝造物主、聖母瑪莉亞和聖子耶穌的讚歌、頌詞、禱詞，以及對信仰的思想、意念，都是與天主感應下的自然流露。但這宗教情懷不僅直接明確地展現在她皈依後的宗教詩中（如〈聖母讚歌〉），早在皈依以前的青春時期（如《水上琴聲》時期），她的宗教情懷便間接隱微地反映在對大自然與對人生的熱愛。皈依後的張秀亞更如天上使者，以感恩的心將愛融於生活之中，正如她的散文詩中所言「願我今後的生活／能溶融在　主的聖愛裡／願我所言、所行、所思／變成了立體的熱誠禱詞」，並以具體的行動－文學創作將對天主的愛散播於生活周遭的人、事、物，使之成為文學創作的題材，化現實之醜為「地上天國」之美的浪漫詩句。她的詩大多運用了寄情於景，情景交融互滲，或象徵，或擬人，或直抒胸臆等等的表現技巧，在天主的聖愛懷抱裡，以及與大自然交成的生命基調中，無論人生境遇是悲是喜、是苦是樂，是順是逆，都轉化為含蓄收斂、委婉寧靜的「立體禱詞」。正是這自始至終的宗教情懷，以及後來的信仰力量，造就了真摯、良善、純美、聖潔、博愛的詩人張秀亞。

Zhang Xiuya composed 213 poems throughout her life. Most of her poems were collected in her poetry anthologies including The Sound of Music above Water The Autumn by the Pond, My Water Ink Vignette, and Another Day in Love. The rest of her poems either remained undated or unpublished until National Museum of Taiwan Literature published The Anthology of Zhang Xiuya and selected those ＂uncollected poems＂ in the first book of the series, ＂Poems,＂ and virtually made this ＂Book of Uncollected Poems＂ the fifth book of her poetry anthology. Though not overwhelming in numbers in her oeuvre-15 poems address directly to religious themes and a total of 35 poems that referred to her religious belief in general-without doubt, one can assume that her religious belief is important to her spirit, discourse, creativity, and her life. Zhang Xiuya was a faithful Catholic thus it was natural that she wrote odes, psalms, and prayers for the Lord, the Mother of Christ, and Jesus Christ, and for her belief, ideology, and faith. All these are but the intuitive revelations of her correspondence with her Lord in Heaven. Her religious concerns were clearly expressed in her religious poems (e.g. ＂Psalm to the Mother of Christ＂) after she embraced Catholicism, yet even when she was young-around the time she published The Sound of Music above Water, she had more or less revealed her religious concerns through her praise of Nature and her love to her life. In her prose poem, Zhang had made manifest her wishes: ＂Wish my life from now on, would converge on the Lord's sacred love. Wish my word and my deeds, become multifaceted fervor prayer.＂ Turning her love of the God into literary works and disseminating this love to everyone and everything around her, Zhang had turned the shame of reality into beautiful lyrical lines that belong to this ＂Earthly Heaven.＂ Most of Zhang's poems incorporated techniques expressing and mixing her feelings and emotions through descriptions of scenes and landscapes. In her poetry, Zhang uses symbols, makes immediate expressions or personifies inanimate things in order to transform her experience in life-her love for the all-loving Lord and her correspondence to nature, into implicit, introversive, euphemistic, and tranquil ＂multifaceted prayers.＂ It is this unswerving religious concern and her might in religion that complete this sincere, virtuous, beautiful, blessed, and philanthropic poet.