The very first time. in the 1st verses of Bereshit Genesis, God produces light and “there was night and morning” (Genesis 1:5) The rabbis reasoned that when the Torah, the item of divine revelation, stated that the day that is first with night, that has to have already been God’s intention, for “days” to begin with at sunset. When the sky is streaked with all the diminishing Friday sunshine, in Jewish houses around the globe, candles are illuminated, blessings are stated and Shabbat is welcomed. As well as in synagogues, the Friday Ma’ariv solution starts with a few hymns, Psalms, and blessings collectively referred to as Kabbalat Shabbat/ Welcoming the Sabbath.
A Kaddish said after learning in a group, in honor of our teachers in orthodox congregations, Kabbalat Shabbat consists of Psalms 95 through 99, Psalm 29, the hymn Lecha Dodi, Come my beloved, Psalms 92 and 93, a lengthy reading from the Talmud passages governing the Sabbath, placed here to separate Kabbalat Shabbat from Ma’ariv, and both the Mourner’s Kaddish and Kaddish de-Rabanan.