Deuteronomy 26:14

I have not eaten of it in the days of my mourning, nor separated from it for the unclean, neither have I given of it a covering for the soul of the dead: we have hearkened to the voice of the Word of the Lord; I have done according to all that Thou hast commanded me.

I have not eaten it in my mourning as in “son of my mourning” [Genesis 35: 18] or “bread of mourners [Hosea 9: 4].” This word’s meaning (to which I alluded in my treatise on the Hebrew language) is the same as “while I was mourning” — to wit: I did not eat anything sanctified as the tithe, while I was in mourning.

Neither did I remove any of it In other words, I did not waste anything holy

when ritually impure — i.e., on anything that was ritually impure.

for a dead person here means for the needs of a dead person (although some people believe that this term is an oblique reference to idolatry). The reason behind all of these declarations is that it is forbidden to bring out one’s produce for any purpose whatever before first giving away the tithe, which is holy. It would be disrespectful to use the remainder of the produce first, even if one were to use it for a ritually impure purpose. And just as I have carefully guarded my produce, in order to extract the holy portion therefrom, so may God guard our country — hence the reference to the land

I HAVE NOT EATEN THEREOF IN MY MOURNING. Even though the avowal included all tithes, as the Rabbis interpreted: “I have also given it unto the Levite, and unto the stranger, to the fatherless, and to the widow etc.,”, this is the tithe of the Levite [i.e., the First Tithe]. I have ‘also’ given it, this is the terumah (the heave-offering), [given by the Israelite to the priest] and the heave-offering of the tithe [given by the Levite to the priest]. And unto the stranger, to the fatherless, and to the widow, this refers to the Poorman’s Tithe, gleanings, the forgotten sheaf, and the corner of the field” (Maaseir Sheini 5:10). — the statement I have not eaten thereof in my mourning refers only to the hallowed things [mentioned at the beginning of the preceding Verse 13: I have put away ‘the hallowed things’ out of my house] which refers to the Second Tithe and fourth-year’s plantings which may not be eaten in mourning and in a state of impurity.

לא אכלתי באוני ממנו, the word און is used here in the same sense as in Job 20,10 ידיו תשבנה אונו, where it refers to the proceeds of a robbery, i.e. “his own hands must give back his wealth.” We also find it used in this sense in Hoseah 12,9 מצאתי און לי, “I have become rich.” (the riches derive from robbery) This is the plain meaning of the line.