Why Sinai Poured Out Every Commandment Like Oil From a Jar

[(Exodus 18:1:) AND JETHRO HEARD.] This is what Scripture says (in Song of Songs 1:3): "FOR THE FRAGRANCE OF YOUR GOODLY OILS, etc." Rabbi Yannai said: To the first ones You gave the fragrance of commandments. To Adam You gave seven commandments. To Noah and his sons You gave seven commandments. You gave them the fragrance of commandments. But when we came to Sinai, like a person who pours from the mouth of the jar, You poured out for us all the commandments, as it is said (ibid.): "YOUR NAME IS OIL POURED OUT."