Midras Imamat 19:12: Midrash Tanchuma, Midrash Tanchuma Buber, Mekhilta DeRabbi Yishmael & Sifra

(Lev. 19:2:) “Speak unto the whole congregation of the Children of Israel, and say unto them, ‘You shall be holy.’” What reason did He have to speak this parashah in an assembly?⁵ Lev. 7:3; Lev. R. 24:5. Why did He not say, “Speak unto the Children of Israel,” as in the rest of the parashiot,⁶I.e., in Exod. 14:2, 15; 25:2; 31:13 Lev. 1:2; 4:2; 7:23, 29; 12:2; 15:2; 18:2; 23:2, 10, 24, 34; 25:2; 27:2; Numb. 5:6, 12; 6:2; 9:10; 15:2, 18, 38; 17:17; 19:2; 33:51; 35:10. rather than “[Speak] unto the whole congregation of the Children of Israel?” Because all of the [ten] commandments are included within it. How? In the commandments it is written (in Exod. 20:2 = Deut. 5:6), “I [am] the Lord your God”; and here (in Lev. 19:2), “I [am] the Lord your God.” In the commandments it is written (in Exod. 20:3 = Deut. 5:7), “You shall have no [other gods beside Me]”; and here (in Lev. 19:4), “Do not turn unto idols.” In the commandments it is written (in Exod. 20:7 = Deut. 5:11), “You shall not take [the name of the Lord your God in vain]”; and here (in Lev. 19:12), “You shall not swear falsely by My name.” In the commandments it is written (Deut. 5:12), “Guard the Sabbath day”; and here it is written (in Lev. 19:3), “You shall keep My Sabbaths.” In the commandments it is written (in Exod. 20:12 = Deut. 5:16), “Honor your father and your mother”; and here it is written (in Lev. 19:3, cont.), “you each shall fear his mother and his father.” In the commandments it is written (in Exod. 20:13 = Deut. 5:17), “You shall not murder”; and here it is written (in Lev. 19:16), “you shall not stand over the blood of your neighbor.” in the commandments it is written (in Exod. 20:13 = Deut. 5:17), “you shall not commit adultery”; and here it is written (in Lev. 19:2), “You shall be holy.“ In the commandments it is written (in Exod. 20:13 = Deut. 5:17), “you shall not stea”l; and here it is written (in Lev. 19:11), “You shall not steal.” In the commandments it is written (in Exod. 20:13 = Deut. 5:17), “you shall not bear [false witness against your neighbor]”; and here it is written (in Lev. 19:16), “You shall not go around as a slanderer among your people.” In the commandments it is written (in Exod. 20:14 = Deut. 5:18), “You shall not covet”; and here it is written (in Lev. 19:13), “You shall not oppress your neighbor, and you shall not rob him.” Here all of the [ten] commandments are included within [it]. It is therefore stated (in Lev. 19:2), “Speak unto the whole congregation [of the Children of Israel].”

In the Commandments it is written (in Exod. 20:2 = Deut. 5:6): I < AM > THE LORD YOUR GOD; and here (in Lev. 19:2): I < AM > THE LORD YOUR GOD.
In the Commandments it is written (in Exod. 20:3 = Deut. 5:7): YOU SHALL HAVE NO < OTHER GODS BESIDE ME >; and here (in Lev. 19:4): DO NOT TURN UNTO IDOLS.
In the Commandments it is written (in Exod. 20:7 = Deut. 5:11): YOU SHALL NOT TAKE < THE NAME OF THE LORD YOUR GOD IN VAIN >; and here (in Lev. 19:12): YOU SHALL NOT SWEAR FALSELY BY MY NAME.
In the Commandments it is written (in Exod. 20:8; cf. Deut. 5:12): REMEMBER [THE SABBATH DAY]; and here it is written (in Lev. 19:3): YOU SHALL KEEP MY SABBATHS.
In the Commandments it is written (in Exod. 20:12 = Deut. 5:16); HONOR YOUR FATHER AND YOUR MOTHER; and here it is written (in Lev. 19:3, cont.): YOU EACH SHALL FEAR HIS MOTHER AND HIS FATHER.
In the Commandments it is written (in Exod. 20:13 = Deut. 5:17): YOU SHALL NOT MURDER; and here it is written (in Lev. 19:16): YOU SHALL NOT STAND OVER THE BLOOD OF YOUR NEIGHBOR.
In the Commandments it is written (in Exod. 20:13 [14] = Deut. 5:17): YOU SHALL NOT COMMIT ADULTERY; and here it is written (in Lev. 19:2): YOU SHALL BE HOLY.
In the Commandments it is written (in Exod. 20:13 [15] = Deut. 5:17): YOU SHALL NOT STEAL; and here it is written (in Lev. 19:11): YOU SHALL NOT STEAL.
In the Commandments it is written (in Exod. 20:13 [16] = Deut. 5:17): YOU SHALL NOT BEAR < FALSE WITNESS AGAINST YOUR NEIGHBOR >; and here it is written (in Lev. 19:16): YOU SHALL NOT GO AROUND AS A SLANDERER AMONG YOUR PEOPLE.
In the Commandments it is written (in Exod. 20:14 [17] = Deut. 5:18): YOU SHALL NOT COVET; and here it is written (in Lev. 19:13): YOU SHALL NOT OPPRESS YOUR NEIGHBOR, AND YOU SHALL NOT ROB HIM.

(Ibid. 7) "You shall not take the name of the L–rd your G–d in vain": A vain oath, too, was included in (Leviticus 19:12) "You shall not swear falsely in My name," and Scripture removed it from its class to exempt it from an oath, viz. (Leviticus 5:4) "Or if a soul swear in uttering with his lips, etc.", Scripture being more stringent with it (a vain oath) and exempting it from an offering — I would think that just as it is exempt from an offering, it is exempt from stripes. It is, therefore, written "You shall not take the name of the L–rd your G–d in vain" — It was exempt from an offering, but not from stripes.