That it spread no further (hina mē epi pleion dianemēthēi). First aorist passive subjunctive of dianemō, to distribute with hina mē, negative purpose.
Let us threaten them (apeilēsōmetha autois). Hortatory aorist middle subjunctive of apeileō, old verb (note middle voice). In the N.T. only here and 1Pe 2:23.
That they speak henceforth to no man in this name (mēketi lalein epi tōi onomati toutōi mēdeni anthrōpōn). Indirect command with the infinitive and double negative (mēketi, mēdeni). They will not say “Jesus,” but make a slur at “this name,” contemptuous use of houtos, though they apparently do mention the name “Jesus” in Act 4:18.