About daybreak (hupo ton orthron). From ornumi, to stir up, to arouse, so the dawn (Luk 24:1; Joh 8:2). Old word, but in the N.T. only these three passages. “Under the dawn” or “about dawn.” Sub lucem. The temple doors would be open for early worshippers and traffickers (Joh 2:14).
Taught (edidaskon). Imperfect active, began to teach.
The council (to sunedrion). The Sanhedrin.
The senate (tēn gerousian). From gerōn, an old man, just as the Latin senatus is from senex, old. Like the gerontes in Homer and the Elder Statesmen in Japan. Apparently the senate of the people were also part of the Sanhedrin and the use of “and” (kai) is explanatory and adds this item in particular. Page thinks that this group of elders were not members of the Sanhedrin at all.
To the prison house (eis to desmōtērion), another word for prison (tērēsis dēmosia in Act 5:18, hē phulakē in Act 5:19). See also Act 5:22, Act 5:23, Act 5:25. This from desmos, bond, and tēreō, to keep, place where bound men are kept.