Easton's Bible Dictionary (1897)
The first-fruits of the ground were offered unto God just as the first-born of man and animals. The law required, (1.) That on the morrow after the Passover Sabbath a sheaf of new corn should be waved by the priest before the altar (Lev. 23:5, 6, 10, 12; 2:12). (2.) That at the feast of Pentecost two loaves of leavened bread, made from the new flour, were to be waved in like manner (Lev. 23:15, 17; Num. 28:26). (3.) The feast of Tabernacles was
an acknowledgement that the fruits of the harvest were from the Lord (Ex. 23:16; 34:22). (4.) Every individual, besides, was required to consecrate to God a portion of the first-fruits of the land (Ex. 22:29; 23:19; 34:26; Num. 15:20, 21). (5.) The law enjoined that no fruit was to be gathered from newly-planted fruit-trees for the first three years, and that the first-fruits of the fourth year were to be consecrated to the Lord (Lev. 19:23-25).
Jeremiah (2:3) alludes to the ordinance of “first-fruits,” and hence he must have been acquainted with the books of Exodus, Leviticus, and Numbers, where the laws regarding it are recorded.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
FIRST'-FRUITS. The first-fruits of harvest, of the vintage, the threshing-floor, the wine-press, the oil-press, the first baked bread of the new crop, and the first fleeces of the flock, were required by God to be given for the use of his ministers, the priests. Ex 23:19; Num 15:19-21; Ex 18:12-13. These offerings were brought to the temple. By making this consecration of the first-fruits the entire produce was consecrated, as the nation had been
by the consecration of the first-born. No particular quantity was designated, but it is supposed a sixtieth part of the whole was the least measure. The manner of offering the first-fruits is prescribed Lev 23:10-14. A sheaf of the first ripe barley was brought on the morrow after the Passover Sabbath, and waved by the priest before the Lord; and after being threshed in a court of the temple, a handful of it was cleansed and roasted and pounded
in a mortar. Oil was mingled with it, and it was then waved before the Lord in the name and behalf of the nation, as an acknowledgment of dependence and gratitude. Until this was done the harvest remained untouched. During the times of apostasy after Solomon this ordinance was neglected, but Hezekiah awakened the national conscience on this subject, 2 Chr 31:5-12. After the Captivity, Nehemiah appointed places for the reception of the
first-fruits of both kinds (raw produce and prepared produce). Neh 10:35, Neh 10:37; Neh 12:44. The prophets insist on the duty of offering them. Eze 20:40; Jer 44:30; Eze 48:14; comp. Rev 14:4. Fruit trees were unplucked for three years. The fourth year's yield was given to God as the first-fruits, but from the fifth year the fruit was the owner's, Lev 19:23-25. The first-fruits were emblematical of abundance and excellence, Rom 8:23, and also
the earnest or sample of a full harvest at hand, 1 Cor 15:20.