He shall rule (poimanei). Future active of poimainō, to shepherd (from poimēn, shepherd), also from Psa 2:8. See again Rev 7:17; Rev 12:5; Rev 19:15.
With a rod of iron (en rabdōi sidērāi). Continuing the quotation. Instrumental use of en. Rabdos (feminine) is the royal sceptre and indicates rigorous rule.
The vessels of the potter (ta skeuē ta keramika). Old adjective, belonging to a potter (kerameus, keramos), here only in N.T.
Are broken to shivers (suntribetai). Present passive indicative of suntribō, old verb, to rub together, to break in pieces (Mar 14:3).