The Apostles were with the Lord Jesus after His resurrection while He spoke of the things concerning the kingdom: "To whom also he shewed himself alive after his passion by many infallible proofs, being seen of them forty days, and speaking of the things pertaining to the kingdom of God" (Acts 1:6) So if anyone could be considered an expert on the kingdom it was them and they believed that the Lord would "restore" the kingdom to Israel: "When they therefore were come together, they asked of him, saying, Lord, wilt thou at this time restore again (apokathistēmi) the kingdom to Israel?" (Acts 1:6). This Greek word apokathistēmi means "to restore to its former state, to be in its former state" (Thayer's Greek English Lexicon). Since the kingdom of which the Apostles spoke was originally an "earthly" kingdom then when it will be resored it will once again be an "earthly" kingdom. It is not difficult to understand that the kingdom which will be resoted to Israel is this one: "Then sat Solomon upon the throne of David his father; and his kingdom was established greatly" (1 Ki.2:12).