ברוך אתה ה אלוהינו מלך העולם אשר קדשנו במצותיו וצונו להדליק נר של שבת
Blessing over the Shabbat Candles
Blessed are you, Adonai our God, Sovereign of the universe, who hallows us with mitzvot, commanding us to kindle the light of Shabbat.
(ח) זָכוֹר אֶת־יוֹם הַשַּׁבָּת לְקַדְּשֽׁוֹ
(1) יהא זהיר לעשות נר יפה, ויש מכוונים לעשות שתי פתילות, אחד כנגד זכור ואחד כנגד שמור.
Shulchan Aruch, Orach Chayyim 263:1
One should be careful to use a nice candle/lamp, and there are those that prepare two wicks (lamps), one for Zachor, and one for Shamor.
רש"י על שבת כ״ה ב: הדלקת נר בשבת - שלא היה לו ממה להדליק ובמקום שאין נר אין שלום שהולך ונכשל והולך באפילה:
Rashi on Shabbat 25b Lighting the Sabbath Candle
That he didn't have anything with which to light. And in a place where there is no candle, there is no "Shalom", that one walks and stumbles and walks in darkness.
Jennifer Breger, Ritualwell
Perhaps the most powerful image of Shabbat is of lighting candles... When we light Shabbat candles, we are reenacting God's creation of light recorded in the first chapter of Bereishit. According to our Rabbis, Shabbat itself is the generator of light in the world, "And God blessed the Sabbath day. How did God bless it? With light. When the sun set on the night of Shabbat, the light continued to function"(Bereishit Rabbah 11,2). The radiant light of Shabbat is a theme of Jewish sources through the ages. Not only does one's house shine on Shabbat but one's face is said to have a special radiance.