This guide is for churches uploading audio files via WordPress. If you’re embedding sermon media from a service like SoundCloud or YouTube then this does not apply because you media is already hosted externally. You do not have to host audio files externally. It is perfectly fine (and more common) to host your audio on your web hosting account with your website, but there are benefits to hosting externally as well.
There is a plugin called WP Offload Media (also see free version) that will automatically move your media files (any file you upload to WordPress) to an external file hosting service after you upload via WordPress. This way you can add sermons to WordPress as usual but benefit from external file hosting. It supports DigitalOcean Spaces and Amazon S3. We recommend DigitalOcean Spaces because it is easier to use than Amazon S3, relatively inexpensive and better suited to serving your files without extra configuration.
See the WP Offload Media Digital Ocean Spaces Quick Start Guide for information on how it works.
Tip: We recommend compressing your sermon audio to be under 20 MB each. Generally, a one hour audio clip can be made less than 20 MB and as low as 5 MB. This would put about 10 years of weekly sermons at 10 GB. Most hosts will allow this much storage but it will also make website backups more cumbersome than perhaps they need to be. A smaller size is also helpful to listeners on slow connections (rural areas, cellular connections, etc.).