You can do it using html.
First, you need to upload the image you want to display to your media library (ex. “greencheck.jpg”)
…then you want the html to look something like this.
<img src="<strong>https://yourdomain.com/wp-content/uploads/2013/10/greencheck.jpg</strong>" alt="green check" width="5" height="5" />i'm cheap
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The file path (part in bold) you can find by going into your media library, clicking on the image you uploaded, and copying it from there (find it in the bottom right once you click on the image.
