Describing the voice of a speaker?

This is an excerpt from a story I'm currently working on:

His nails move gently along the flesh of my throat, coming to rest under my jawbone. “Rise.” Within just a single word, I hear almost undeniably divine authority.

It just sounds awkward to me. I feel like there should be a comma after "Rise", but I'm not using anything like "he said" to make it fit... Is it incorrect to place a period at the end of dialogue in the way that I have here? Is anything else wrong? I do apologize if this is a bit of a silly question, but something about it seems off to me. Advice of any kind is very appreciated!

Grammar bug time.

The use of the period is fine. You would use a comma if you were continuing with a speech tag.

I think what's awkward is the sentence that follows. Grammatically each clause should be able to stand on its own as a complete thought. 'Within just a single word...' doesn't mean anything on its own, so it should be one complete sentence to make sense.

An added note- be bold in your writing. 'Almost' is a word we use when we're shy to say something for certain. 'I hear undeniably divine authority' carries so much more impact than 'almost undeniably divine.' The same with 'just'. When you say 'a single word' it is more significant than 'just a single word.'

I really want to read what this is from now =D This character sounds beautifully deadly.

@Tenyo got everything grammatically correct, but I wanna talk about the wording you've got going on here.
You feel like it's awkward because it is.

“Rise.” Within just a single word, I hear almost undeniable divine authority.

Within is a really weird use here. I would use "With just a single word,"
Why is it divine? Obviously we haven't heard the rest of the story, but unless it's actually something divine, I'd delete the word.
So if you took all my editing, it would be

“Rise.” With just a single word, I hear undeniable authority.

Doesn't that flow much better?
-Spark

The tips above are sound in their own rights, but let me share with you a phrase that I like to use: "When in doubt, saturate with imagery."
Of course, when I say saturate, I don't mean for you (or anyone else, for that matter) to tack on six different adjectives to a single noun and call it good. However, this kind of sentence strikes me as one that needs a bit more action to it. Here's an example.

Instead of this...

"Within just a single word, I hear almost undeniably divine authority."

... try something more like this.

"The sheer amount of undeniable authority within that single spoken word causes me to shiver involuntarily, though whether it's caused by fear or anticipation, I don't know."

It may not seem like a big change, but if the spoken word is really as undeniably authoritative as you intend it to be, give your character a bit of a reaction to it. That way, you will make the reader more inclined to believe that the word is important.

Thank you all so much! I feel much better about this now

@Tenyo The character certainly is beautifully deadly, I'd love to let you read it upon completion!

@SparkToFlame Interesting... I originally had very similar wording to your suggestion, but ended up changing it. I use the word divine to emphasize the god-like characteristics of the character, an ever-present theme in the story. He isn't actually a god, but named himself after one and, in so doing, gets closer and closer to actually becoming the god himself.

@Crunchman99 That description is incredible and spot-on. I have quite a bit of description in the sentences surrounding this one, but can definitely see how it would be much more powerful in the same sentence.

LoseControl wrote:
His nails move gently along the flesh of my throat, coming to rest under my jawbone. “Rise.” Within just a single word, I hear almost undeniably divine authority.

I would write instead "his nails move gently along the flesh of my neck." It sounds a little better that way. I guess because when I think of throat, I think of it on the inside.