道教的祭祀儀式習稱為齋醮，有關齋醮的一系列法事內容稱為科儀。青詞是齋醮儀式中獻給天神的奏告文書，是道教科儀常用的祭祀詞文。青詞產生於唐代太清宮的齋醮，隨唐宋元明國家齋醮祭祀而盛行。青詞是表達齋主心意的祭祀文書，有用青紙朱書敬獻神靈的儀格，其顏色蘊涵著宗教象徵意義。青詞的撰寫者多為歷代文士，唐宋時期翰林院的翰林學士，有為國家齋醮撰寫青詞的職責。道教青詞有齋儀與醮儀青詞的區分，以適應道教先齋後醮的科儀格式。道教關於青詞的撰寫及投送，有青詞式、青詞關等科法規定，以保證道教履行國家宗教的祭祀職能。從道教青詞的具體祈禳內容，可知古代道教的濟世度人活動，青詞是道教神仙信仰的文學化表達，它蘊涵著道教的濟度之「道」。

Sacrificial rituals in Taoism are customarily refereed to as zhaijiao (齋醮 fast and abstention), while the actual contents of the rituals are called keyi (科儀 ritualistic patterns). The memorial on green paper (qingci青詞) ,a sacrificial poem commonly used in Taoist ritual, is a document presented to super­natural beings in heaven during a ritual. Both the green of the paper and the red of the ink have symbolic religious meaning. They were first used during rituals held at the Taiqing gong 太清宮 during the Tang dynasty and came into widespread use in royal sacrificial activities from the Tang to the Ming dynasties. A memorial on green paper expresses the wishes of the host of the ritual, although the actual authors were generally prominent literati of the time, with members of the Imperial Academy (hanlin yuan翰林院) being charged with writing such documents during the Tang and Song dynasties. Differences between poems written for zhai rituals and jiao rituals reflect the keyi ordering that calls for the former to precede the latter. There are also strict ritualistic requirements for the writing and presenting of works of this nature that were designed to ensure that Taoism fulfilled its political position as the religion of the royal families. From the contents of these works, a literary expression of Taoist religious belief, we can also get a glimpse of how Taoism went about achieving its purpose of saving lives and helping people.