Read Lecha Dodi on Sefaria for the surrounding biblical/liturgical context.
Born in Salonika (Greece), Alkabetz migrated as a young scholar to Safed, the Galilean mountain town that became the global center of Kabbalah in the mid-16th century. There he joined the circle of Rabbi Moshe Cordovero (his brother-in-law) and was a senior figure when the young Rabbi Isaac Luria (the Arizal) arrived to revolutionize Kabbalistic thought.
Alkabetz wrote many poems, but only one survived into universal liturgy: Lecha Dodi. The custom in Safed was for the kabbalists to walk out of the synagogue into the fields on Friday afternoon, dressed in white, to physically greet Shabbat as she descended over the hills. Lecha Dodi was composed for that procession. Within 50 years the custom spread to every Jewish community.
The full poem moves through stages:
Stanza 1: "Shamor and Zachor", the dual commandment.
Stanzas 2-3: the call to wake up Jerusalem from her ruined state, "Shake off the dust, arise!"
Stanzas 4-5: the in-gathering of the exiles, the rebuilding of the Temple.
Stanzas 6-7: the defeat of Israel's oppressors, the climactic political/messianic stanzas.
Stanza 8: the joy of the people in their restored land.
Stanza 9: Bo'i b'shalom, "Come in peace, crown of her husband", the moment of greeting, when the congregation rises and turns to face the synagogue door.
So Lecha Dodi is not only a wedding song, it's a compact messianic vision in 9 stanzas: from exile to rebuilding to gathering to redemption to encounter.
The most visually distinctive moment in Friday-night liturgy: at the start of the 9th stanza, every member of the congregation rises and turns 180° to face the back of the synagogue (the entrance). The bows alternate: bow right for "Bo'i kalah" (come, bride), bow left for "Bo'i kalah" repeated, bow forward for the third repetition. Then turn back to face the front of the synagogue. The bride has entered.
This turn is one of the few moments in mainstream Jewish prayer that uses choreography. Different communities do it slightly differently; the body language is the message. After this turn, Shabbat is functionally present in the room.