The "holy thing" in this verse is the food that is tithed to G-d or the food that is offered as part of a sacrifice to G-d: it is considered a breach of holiness to benefit from these things. If a person eats something that is devoted to G-d then he is to repay what was eaten plus one-fifth (20%) and bring an offering of a ram for his guilt.For more details about the sacrifices we highly recommend the article from Psalm11918.org regarding What Scripture Says About the Sacrifices. It provides details about the guilt offering: what the offering was and when it was used. They also have a separate article regarding the purpose of the sacrifices.
The Literal Commandment
He shall make restitution for that which he has sinned against the holy thing, and shall add to it a fifth part of it and give it to the priest. The priest shall then make atonement for him with the ram of the guilt offering, and it will be forgiven him. (Leviticus 5:16)
The "holy thing" in this verse is the food that is tithed to G-d or the food that is offered as part of a sacrifice to G-d: it is considered a breach of holiness to benefit from these things. If a person eats something that is devoted to G-d then he is to repay what was eaten plus one-fifth (20%) and bring an offering of a ram for his guilt.
For more details about the sacrifices we highly recommend the article from Psalm11918.org regarding
What Scripture Says About the Sacrifices. It provides details about the guilt offering: what the offering was and when it was used. They also have a separate article regarding the purpose of the sacrifices.
Messiah Says
Messiah implicitly affirmed this commandment when He spoke about the Law:
"Do not think that I came to abolish the Law or the Prophets; I did not come to abolish but to fulfill. For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished. Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven. (Matthew 5:17-19)
He also affirmed the portion of the commandment that indicated some things are dedicated to G-d and should be set apart:
Then render to Caesar the things that are Caesar's; and to God the things that are God's. (Matthew 22:21)
Pictures of Messiah
This commandment is a picture of righteous judgment. If a person sins against a "holy thing" by taking it and appropriating it for his own use then he is to repay it and add to it one-fifth of its value.
Messiah is the righteous judge (2 Timothy 4:8) who has commanded us to judge with righteous judgment (John 7:24). In this way the commandment pictures Messiah, the righteous judge.
How Messiah Fulfilled
Messiah never sinned (Hebrews 4:15) and never profaned a sacred object so He never had to fulfill this commandment and make restitution for a holy thing.
Traditional Observance
The traditional observance of this commandment was the literal fulfillment in the circumstances when the "holy things" were profaned.
It is understood that this commandment was given to instill awe and reverent fear regarding coming near to objects of holiness: they should not be treated lightly.
Other Notes
Absent the Temple, the Levitical priesthood, and the associated tithes and offerings (the "holy things") which could be eaten, we are unable to sin in this manner and (as a consequence) we are unable to literally fulfill this commandment today.
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