I will corrupt your seed. Henderson, "I will rebuke the seed to your hurt." God would mar the promise of their crops; but, as the priests did not concern themselves with agriculture, such a threat would have had no particular application to them.
It is best, therefore, to take the pointing of some of the versions, and to translate, I will rebuke your arm; i.e. I will take from you the power of performing, or, I will neutralize your official duties, the arm being the instrument of labour, offering, and blessing.
Others consider the threat to be that they should be deprived of their allotted portion of the sacrifice—the breast and shoulder (Le 7:31, 32), or the shoulder, the two cheeks, and the maw (Deuteronomy 18:3).
Septuagint, ἀφορίζω ὑμῖν τὸν ὦμον, "I take from you the shoulder;" Vulgate, Ego projiciam vobis brachium. Orelli takes "seed" in the sense of posterity, seeing here a reversal of such promises as Jeremiah 33:18, Jeremiah 33:22.
Spread dung upon your faces. God will deliver them over to shameful treatment, which shall cover them with contempt. The idea is derived from the filth left in the courts by the victims (see the following clause).
Your solemn feasts (chaggim); ie. the animals slain at the sacrificial feasts. God calls them "your," not "my," because they were not celebrated really in his honor, but after their own self-will and pleasure.
The dung of the sacrificial animals was by the Law carried forth and bunted without the camp (Exodus 29:14; Le Exodus 4:12; Exodus 16:27). One shall take you away with it. They shall be treated as filth, and cast away in some foul spot.