Lekha Dodi, the hymn that gives Kabbalat Shabbat its emotional centre, was written by Shlomo Alkabetz, a member of the sixteenth-century Safed circle of kabbalists, as an acrostic poem spelling his own name across its stanzas, and its central image, going out to greet the Sabbath as a bride, comes directly from a rabbinic phrase the Safed mystics took up and dramatised into an actual physical practice, walking out into the fields at dusk to receive the Sabbath as one would receive an arriving bride at a wedding. Because the service is comparatively young by liturgical standards, composed centuries after the core prayer book had already stabilised, it never fully closed to further composition the way the older fixed services did, and it has kept absorbing new material and new settings ever since: nineteenth and twentieth-century composers wrote fresh melodies for its psalms with unusual freedom compared to other services, and the American rabbi and songwriter Shlomo Carlebach's tunes from the mid-twentieth century onward became so widely adopted across Orthodox, Conservative and Reform congregations alike that a version of Kabbalat Shabbat sung entirely to Carlebach melodies, sometimes called a Carlebach minyan, is now a recognised and separately named style of service in its own right.
Reform and Jewish Renewal communities have gone further still, restructuring the service with guitar accompaniment, congregational singing and altered wording, changes the more traditional services in the daily prayer cycle have generally resisted, which makes Kabbalat Shabbat, alone among the services described here, a living and still-changing composition rather than a fixed inheritance.