A.T. Robertson Commentary Matthew 13:25

"but while men slept, his enemy came and sowed tares also among the wheat, and went away." — Matthew 13:25 (ASV)

While men slept (εν τω καθευδειν τους ανθρωπους). Same use of the articular present infinitive with εν and the accusative as in 13:4.

Sowed tares also (επεσπειρεν τα ζιζανια). Literally "sowed upon," "resowed" (Moffatt). The enemy deliberately sowed "the darnel" (ζιζανια is not "tares," but "darnel," a bastard wheat) over (επ) the wheat, "in the midst of the wheat." This bearded darnel, lolium temulentum, is common in Palestine and resembles wheat except that the grains are black. In its earlier stages it is indistinguishable from the wheat stalks so that it has to remain till near the harvest. Modern farmers are gaining more skill in weeding it out.