Exodus 23:16

And the feast of the harvest first-fruits of the work thou didst sow in the field; and the feast of gathering, at the end of the year, when thou hast gathered in thy work from the field.

AND THE FEAST OF HARVEST, THE FIRST-FRUITS OF THY LABORS, AND THE FEAST OF INGATHERING AT THE END OF THE YEAR. I do not know why Scripture mentions the names of the festivals with the definite article since He has not yet commanded about or mentioned them at all till now, and it ought to have said first: “and you shall keep a feast of harvest, the first-fruits of your labors,” just as He said in the Book of Deuteronomy, And thou shalt keep a festival of weeks unto the Eternal thy G-d. But perhaps because He had already said, Three times thou shalt keep a feast unto Me in the year, and further explained, The feast of unleavened bread shalt thou keep… in the mouth of Aviv, [literally: “maturity”] means the month when the grain becomes full in its ripe state (Rashi). It is the month of spring. meaning that you are to make sure that the Passover festival is observed at the beginning of the month of Aviv, He referred back [to these verses] and said, “And as for the other festival, make sure that it be the feast of harvest, the first-fruits of thy labors, and as for the third one, make sure that it be the feast of ingathering, at the end of the year. Now all these festivals are thus named with reference to man’s activities in the field, in order that he give thanks for them to G-d who guards the ordinances of heaven, and brings forth bread out of the earth to satisfy the longing soul, and the hungry soul He hath filled with good., 107:9. This is Scripture’s intention in using here the expression: el pnei Ha’adon Hashem (three times in the year shall all thy males appear — ‘before the Master, the Eternal’), for He is the Master who provides the needs of His servants, and when they take their part from before Him, they come to Him to see what He commands them to do. Thus the expression el pnei is like ‘liphnei’ (“before”) — before the Master. But by way of the Truth, [the mystic teachings of the Cabala], the word pnei is derived from the term panim [literally: “face”], and I have already alluded to the explanation of panim in the Ten Commandments. This is why He said Ha’adon Hashem (the Master, the Eternal), just as He said the second time, the Master, the Eternal, the G-d of Israel. here is not in the grammatical form of construct with the word Hashem; this is evident from the same expression which occurs a second time [in 34:23] where it is written Hashem Elokei Yisrael, thus indicating that here too the word Hashem is not in construct with Ha’adon (Abusaula). Similarly: Behold, the ark of the covenant of the Master of all the earth; Tremble, thou earth, ‘miliphnei’ (at the presence) of the Master. which is suggestive of panim, as mentioned above (Abusaula).

וחג הקציר, the Shavuot festival on which the sacrifices mentioned in Leviticus 23,16-20 including the offering of the two loaves of the first wheat harvest are listed.

בכורי מעשיך, in order to permit use of the new wheat harvest products in the Temple for the gift offerings.

וחג האסיף, the Sukkot festival, a period immediately after the last harvest of the summer has been brought in. The Torah commanded us to sit in the huts in commemoration of the times when instead of having their own crops, the Israelites were in the desert depending on the daily ration of manna. Observance of the festival of חג האסיף, an aspect of the Sukkot festival therefore is a form of thanksgiving. We have learned therefore that all of the three pilgrimage festivals are directly related to the produce of the Holy Land.

בצאת השנה. After all the harvests have been gathered in.