The nation is enjoined to be holy. Many prohibitions and positive commandments are taught:
Prohibitions: Idolatry; eating offerings after their time-limit; theft and robbery; denial of theft; false oaths; retention of someone's property; delaying payment to an employee; hating or cursing a fellow Jew (especially one's parents); gossip; placing physical and spiritual stumbling blocks; perversion of justice; inaction when others are in danger; embarrassing; revenge; bearing a grudge; cross-breeding; wearing a garment of wool and linen; harvesting a tree during its first three years; gluttony and intoxication; witchcraft; shaving the beard and sideburns; tattooing.
Positive: Awe for parents and respect for the elderly; leaving part of the harvest for the poor; loving others (especially a convert); eating in Jerusalem the fruits from a tree's fourth year; awe for the Temple; respect for Torah scholars, the blind and the deaf.
“You shall be holy…” (19:1)
It always struck me, that whenever I had the privilege to meet a great Torah Sage — how normal he seemed. It was, in fact, as if he defined the yardstick of normalcy. After meeting this person, others seemed somewhat less than normal.
The Alshich explains that
Holiness does not consist of mortifying the flesh or of extreme abstinence. Holiness does not mean rolling in ice or lying on a bed of nails. Holiness means being more and more normal. Holy Jews live normal married lives. They eat normally. They breathe normally. However, everything they do is with consideration and within measure.
Holiness means being normal even under the most abnormal situations. It means never compromising with our lower desires, but at the same time recognizing that we are part physical beings. Being holy means resisting that extra, excessive spoonful of cholent, even if the kashrut is top-notch. Above all, holiness means going beyond the technical fulfillment of the mitzvahs. It means sanctifying that which is permitted. When something is outright forbidden, it is much easier to steer clear of it. There’s no room for negotiation with our lower personas. However, when something is permitted, there is always the temptation to push the edge of the envelope. And even though technically one could stay within the letter of the law, the commandment to be holy tells us that there is more to mitzvah observance than the letter of the law. Observing the spirit of the law is itself a mitzvah. That’s what it means to be normal.
- Based on the Ramban