Creating a video from a text and an audio file
The Amara website offers a free service that accepts audio and text files, synchronizes them, and lets you download a .srt file (synchronized SubTitle). Source of suggestion: Photography TutsPlus.
YouTube also accepts text files without time coding as SubTitle files and then you can enable auto-sync, you ought to be able to download a .srt file after processing is completed (not tested by me).

To do it manually (with some automation) try the following.
If you convert the text file to a .ass or .srt file then you can use the following commands:

ffmpeg.exe -i subtitles.srt subtitles.ass
ffmpeg.exe -i video.mp4 -vf ass=subtitles.ass video-new.mp4

That will show the words hardsubbed on the video synchronized with the audio. The video can be a moving image (video) or a static image.
Using a .ass editor allows more control over color and other font features than using .srt files.
Without using a SubTitle Format file you won't get synchronized text.
You can add the audio to a video and upload it to YouTube, then wait 15 minutes, after which YouTube will have used audio recognition to convert the audio to subtitles (with better than 80% accuracy). Then you can download the .srt file from the Video Manager and edit the SubTitle file by comparing it to your (presumably accurate) text file.
If you were hoping for a program that automatically syncs raw text files with audio and makes a video I have found nothing by Googling (outside of pay services).
There are a few questions over at SO, but they remain unanswered.
I will do some more searching and improve this answer in a few hours.
Not a one-mouseclick solution but it's about as automated as I can suggest, for free (other than Amara).
[I welcome Mulvya to edit and improve this answer.]