Vincent's NT Word Studies
31. Thou shalt conceive. See on verse 24.Jesus. See on Matt. i. 21.
Robertson's NT Word Studies
1:31 {Conceive in thy womb} (sullemyei en gastri). Adding en gastri to the verb of #1:24. Same idiom in #Isa 7:14 of Immanuel. {Jesus} (iesoun). As to Joseph in #Mt 1:21, but without the explanation of the meaning. See on Matthew.