Keys of the Kingdom

Look at the release year (1988), and you will have a pretty good idea of the game. Yes, it features a crude two-word parser you sometimes have got to fight with, minimalistic descriptions, and primitive characters. To make things worse, it's a religious game. Therefore, the author constantly tries to convert the player to Christianity, and you might find his blatant and clumsy attempts rather naive (or annoying, if you are less forgiving). Furthermore, the religious theme stipulates that some of the puzzles can't be solved without a reference to The Bible, so that you better keep it handy during playing (if you don't know it by heart, that is).