SEED (Hebrew zera‘, Greek sperma, sporos). There is a threefold use of this word in Scripture:
The farmer held his seed in his upturned garment, casting it out as he walked. Grain was sown in the early winter, after the first rains. Christ’s parable of the sower is well known (Mark.4.1-Mark.4.20; Luke.8.5-Luke.8.15). Land was measured by the amount of seed that could be sown on it (Lev.27.16). The wilderness was “land not sown” (Jer.2.2).
A “man’s seed” (kjv) or “emission of semen” (niv) is a frequent expression in the Hebrew laws of cleanness (Lev.15.16ff.). The New Testament speaks of Christians as having been begotten by God—“not of perishable seed, but of imperishable” (1Pet.1.23; 1John.3.9).
SEED, SEEDTIME. Heb. זֶ֫רַע, H2446, serves for both Eng. words and, like Gr. σπέρμα, G5065, and σπόρος, G5078, is used to indicate both agricultural and human seed, the latter both in a narrow physical sense and as a description of the descendants of a common ancestor.
Seedtime to the farmer in Pal. occurred in late October or November. After the dry, hot summer it was impossible to plow and plant until the early rains (see Rain) had softened the ground and made it workable. Sowing then took place; the Israelite was commanded not to mix his seed in any field or vineyard, but to plant only one crop (Lev 19:19; Deut 22:9), a stricture parallel to that regarding the mixture of human seed by intermarriage with other nations.
The main types of seed and crop grown by the Israelite farmer were wheat, barley, and rye, as well as a number of vegetables. Of these, the barley might be expected to mature first, roughly ten weeks after seedtime, or about the time of the Passover (see Seasons). Maturing of the other crops occurred thereafter, the wheat approximately six weeks after the barley.
Our Lord gave the word “seed” a new dimension of meaning when He said “the seed is the word of God” (Luke 8:11). Thereafter the NT combines the agricultural and physical concepts of the seed in its presentation of spiritual truth; the word of God is sown, takes root in the hearts of men, who are then born as children into the family of God (1 Pet 1:23), and become a spiritual seed or nation.
International Standard Bible Encyclopedia (1915)
(1) For "seed" in its literal sense see Agriculture. Of interest is the method of measuring land by means of the amount of seed that could be sown on it (Le 27:16). The prohibition against using two kinds of seed in the same field (Le 19:19; De 22:9) undoubtedly rests on the fact that the practice had some connection with Canaanitish worship, making the whole crop "consecrated" (taboo). Jer 31:27 uses "seed of man" and "seed of beast" as a figure for the means by which God will increase the prosperity of Israel (i.e. "seed yielding men").
(2) For the transferred physiological application of the word to human beings (Le 15:16, etc.) see Clean; Uncleanness. The conception of Christians as "born" or "begotten" of God (see Regeneration) gave rise to the figure in 1Pe 1:23; 1; Joh 3:9. If the imagery is to be stressed, the Holy Spirit is meant. In I Joh 3:9 a doctrine of certain Gnostics is opposed. They taught that by learning certain formulas and by submitting to certain rites, union with God and salvation could be attained without holiness of life. John’s reply is that union with a righteous God is meaningless without righteousness as an ideal, even though shortcomings exist in practice (1 Joh 1:8).
In Ga 3:16 Paul draws a distinction between "seeds" and "seed" that has for its purpose a proof that the promises to Abraham were realized in Christ and not in Israel. The distinction, however, overstresses the language of the Old Testament, which never pluralizes zera` when meaning "descendants" (plural only in 1Sa 8:15; compare Ro 4:18; 9:7). But in an argument against rabbinical adversaries Paul was obliged to use rabbinical methods (compare Ga 4:25). For modern purposes it is probably best to treat such an exegetical method as belonging simply to the (now superseded) science of the times.