Accordance offers an incredible range of options for customizing the appearance of text. You can set the font, style, text color, background color, leading, paragraph formatting, and more. You can also suppress things like superscript footnote markers, red letter, poetic formatting, etc. One need only open the Text Settings dialog box to see the variety of options available.
In addition to all the options, you can apply these options in a variety of ways: you can make temporary changes to the text in a display pane, you can set the default appearance for an individual Bible text or translation, or you can globally set the default appearance of all your Bible texts. While this flexibility is nice when you need it, it can be a little confusing to people. Hopefully this blog post will help clear up any confusion.
I think the best way to illustrate the different ways to make formatting changes is to have you do an experiment. To set up this experiment, all you need to do is open a search window with your favorite Bible. Then add a parallel pane to that window containing the exact same Bible. In other words, you should have the same Bible appearing in two parallel panes. In the following screenshot, I have two panes displaying the Holman Christian Standard Bible (HCSB):
Now, click in one of the panes, then choose Set Text Display from the Display menu (or use the keyboard shortcut command-T). This will open the Text Settings dialog for that pane. In the dialog, make some change to the display which will be readily apparent. I'm just going to change the background color to "Mint." When you're done making whatever changes you wish to make, click OK.
The display changes you made will immediately be apparent in the selected pane, but will not affect any other panes. In the screenshot below, you can see that while the left pane has the mint green background, the right one does not. I now have two instances of the same Bible with different display settings.
When you make changes to a pane, those changes will remain in effect only as long as you don't change the text displayed in that pane. To see how this works, change the pane you modified to a different Bible, then switch that pane back to the original Bible text. When I switch to a different text and switch back to the HCSB, the HCSB reflects its default display settings, and my mint green background is lost.
Now, let's say I want to make the mint green background appear every time I open the HCSB. To do that, I will use command-T to open the Text settings dialog, and I will once again select Mint from the background color pop-up menu. Only this time, before I click OK, I will click the Use As Default button. An alert will appear asking if I really want to save these settings as the default display for the HCSB. After clicking Save to dismiss this alert box, I can click OK to dismiss the text settings dialog box.
The pane that I am modifying immediately reflects the changes I made, and I once again see the mint green background. However, even though I made this setting the default for the HCSB, the other pane containing the HCSB is not updated to reflect the new setting. The reason for this is that we don't want to override any custom appearance settings which you may have set for open windows or panes, so when you change the default appearance settings for a Bible text, those settings will only apply to any new windows or panes containing that text.
To see that the mint green background is indeed the new default for the HCSB, I can change the other pane to a different text, then change it back to the HCSB. This effectively "new" instance of the HCSB will reflect the new default I just saved.
If I want to set the default display of ALL my Bibles in one fell swoop, I can do that by going to the Preferences dialog and choosing the Text Display settings. Let's say that I want to set all my Bible texts to use the background color named "Book." Once I make that change in the Preferences dialog box and click OK, all new instances of a Bible text will reflect that default setting, but my existing Bible panes remain unchanged until I update them. This is again to avoid overwriting some custom setting or messing up some existing display.
So to summarize, when you modify a pane using the Text Settings dialog and you simply click OK, the changes will apply to that pane only, will appear immediately, and will last only as long as you don't change the text which appears in that pane. Clicking Use As Default in the Text Settings dialog box and then clicking OK will immediately apply your changes to the pane you're modifying, and those changes will be reflected any time you open a new instance of that Bible text, but other open panes containing that Bible will remain unchanged. Finally, when you modify the Text Display settings in the Preferences dialog box, the changes you make will apply to any Bible text you open from that point on, but will not apply to any panes which are already open.
I hope this gives you a better understanding of the different ways you can modify the display settings of your Bibles.