To resolve the issue of the Bible App not updating on your iPhone 13, follow these actionable steps:

1. Force Close the Bible App:
- Swipe up from the bottom of the screen (or double-click the Home button if applicable) to open the app switcher.
- Find the Bible App and swipe it up to close it completely.

2. Check Your Internet Connection:
- Ensure you have a stable internet connection, either through Wi-Fi or mobile data. Open a browser or another app to verify your connectivity.

3. Clear Cache of the Bible App:
- Go to the Settings app on your iPhone.
- Scroll down to find the Bible App.
- Look for options related to clearing cache or data (if available), or proceed to the next step.

4. Sign Out and Sign Back In:
- Open the Bible App.
- Go to your account settings and sign out of your account.
- Close the app, then reopen it and sign back in. This can refresh your account settings and fix potential issues - learn more - learn more.

5. Check for App Updates via the App Store:
- Open the App Store on your iPhone.
- Tap on your profile icon in the top right corner.
- Scroll down to see if there are any pending updates for the Bible App. If there is, tap Update.

6. Restart Your Device:
- Restart your iPhone 13 by holding down the power button until you see the power off slider. Slide to turn off, and then turn it back on after a few seconds.

7. Reinstall the Bible App:
- If none of the above steps work, uninstall the app.
- Long-press the Bible App icon and tap Remove App. Follow the prompts to delete it.
- Revisit the App Store, search for the Bible App, and download it again.

8. Check for iOS Updates:
- Open the Settings app, go to General, and tap on Software Update. Ensure your device is up to date, as newer versions may fix bugs or issues - learn more.

If after all these steps the issue persists, consider reaching out to the app's support for further assistance. Also, checking community discussions can provide insights from others who might have resolved similar issues - learn more.