Unwittingly - Inadvertently, or "through ignorance." Compare Leviticus 4:2 note.

Then he shall put the fifth part thereof unto it - The holy thing of which he has unknowingly eaten shall be fairly valued, and to this value he shall add one fifth more, and give the whole to the priest.

And if a man eat of the holy thing unwittingly,.... Either not knowing that it is an holy thing, or the heave offering, or any thing of that kind; or else is ignorant of the punishment of such an action, as Gersom observes; and this is to be understood of any man that was not a priest, or was not of the priest's family, even any common Israelite; so the Targum of Jonathan, a man of Israel, or an Israelite, one of the common people:

then he shall put a fifth part thereof unto it; a fifth part of the value of what he has eaten, to an equivalent for the whole, that is, he shall pay the full value for what he has eaten, and a fifth part besides:

and shall give it to the priest with the holy thing; the meaning is, that he shall give the fifth part to the priest, with the equivalent for what he has eaten; for he could not give the holy thing itself, but a compensation for it; according to Gersom, he was to give the principal to the priest, whose the holy thing was he ate of, and the fifth part he might give to what priest he would. The Jewish canon, concerning this matter, runs thus; he that ignorantly eats the heave offering pays the principal, and the fifth part; and the same, either he that eats, or drinks, or anoints; and whether the heave offering be clean or unclean, he pays the fifth, and the fifth of the fifth; and he does not pay the heave offering but of common things, rightly ordered, and they become an heave offering, and the compensation of it; and if the priest would forgive, he may not (p).

(p) Misn. Trumot, c. 6. sect. 1.

But if any one (i.e., a layman) should eat unawares of that which was sanctified, he was to bring it, i.e., an equivalent for it, with the addition of a fifth as a compensation for the priest; like a man who had sinned by unfaithfulness in relation to that which was sanctified (Leviticus 5:16). - In the concluding exhortation in Leviticus 22:15 and Leviticus 22:16, the subject to יחלּלוּ (profane) and השּׂאוּ (bear) is indefinite, and the passage to be rendered thus: "They are not to profane the sanctified gifts of the children of Israel, what they heave for the Lord (namely, by letting laymen eat of them), and are to cause them (the laymen) who do this unawares to bear a trespass-sin (by imposing the compensation mentioned in Leviticus 22:14), if they eat their (the priests') sanctified gifts." Understood in this way, both verses furnish a fitting conclusion to the section Leviticus 22:10-14. On the other hand, according to the traditional interpretation of these verses, the priesthood is regarded as the subject of the first verb, and a negative supplied before the second. Both of these are arbitrary and quite indefensible, because Leviticus 22:10-14 do not refer to the priests but to laymen, and in the latter case we should expect אליהם ישׂאוּ רלא (cf. Leviticus 22:9) instead of the unusual אותם השּׂאוּ.

And if a man eat of the holy thing unwittingly, then he shall put the {g} fifth part thereof unto it, and shall give it unto the priest with the holy thing.

(g) He shall give that and a fifth part over.

22:14 Unto it - Over and above the principle, and besides the ram to be offered to God, Lev 5:15. And shall give unto the priest the holy thing - That is, the worth of it, which the priest was either to take to himself or to offer to God, as the nature of the thing was.

14. if a man eat of the holy thing unwittingly-A common Israelite might unconsciously partake of what had been offered as tithes, first-fruits, &c., and on discovering his unintentional error, he was not only to restore as much as he had used, but be fined in a fifth part more for the priests to carry into the sanctuary.

22:1-33 Laws concerning the priests and sacrifices. - In this chapter we have divers laws concerning the priests and sacrifices, all for preserving the honour of the sanctuary. Let us recollect with gratitude that our great High Priest cannot be hindered by any thing from the discharge of his office. Let us also remember, that the Lord requires us to reverence his name, his truths, his ordinances, and commandments. Let us beware of hypocrisy, and examine ourselves concerning our sinful defilements, seeking to be purified from them in the blood of Christ, and by his sanctifying Spirit. Whoever attempts to expiate his own sin, or draws near in the pride of self-righteousness, puts as great an affront on Christ, as he who comes to the Lord's table from the gratification of sinful lusts. Nor can the minister who loves the souls of the people, suffer them to continue in this dangerous delusion. He must call upon them, not only to repent of their sins, and forsake them; but to put their whole trust in the atonement of Christ, by faith in his name, for pardon and acceptance with God; thus only will the Lord make them holy, as his own people.