I'm looking for feelings about shifting between active and passive voice in a particular work. Not shifting regularly, but occassionally. Say, for instance, I was writing in the active voice and wanted to shift to passive to achieve a desired sentence structure. Say I wanted to lead a sentence with the name of a main character, but doing so required me to shift to passive voice. For example:

"Tony was rushed by David."

as oppossed to . . .

"David rushed Tony."

Would this sentence be grammatically acceptable in an active voice piece?

The passive voice is always grammatically acceptable; instead, you should ask whether or not it is stylistically acceptable.
People often recommend the active voice because it is clearer, more concise, and more vivid. But there is no law saying that you can't use the passive voice when you want or need to, and there's no law saying that you must stick to one voice throughout one composition. Unlike with tenses, you are free to switch between voices whenever your Muse tells you to do so.
And in many cases, the passive voice is in fact more appropriate. For example, if you were talking about a famous person, you would probably say that he was born in 1956, not that his mother bore him in 1956. Why? Because he himself is the one you're talking about, and the mention of his mother just takes the reader's attention away from the point by adding another person as if she were really, really significant. I mean, if you're leading up to two paragraphs about his mother, then sure, do that, but probably, you're just giving his date of birth, and so nobody really cares about his mother right now. (Sorry, Famous Mom Lady.)
The decision to use the active or passive voice all depends upon the context and the particular slant you want to give your statement. In general, the active voice is stronger and more concise, and in general, you want to be stronger and more concise, so in general, you should use the active voice. But there are certainly times when this is not the case; so at such times, feel free to use the passive voice.
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What if you wanted to continue the story of his life, would you also be using the passive?
No no, of course not! Remember, you don't have to be consistent with voices as you do with tenses. You can decide which voice to use on a sentence-by-sentence basis.
I have a nasty suspicion that my tedious prolixity has merely served to confuse the matter further. Sorry if I did, folks!
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You are completely wrong. I would like you to continue the story so that we could see how tenses are used.
Completely wrong how? With what I said about tenses or what I said about voices?
I believe she's saying you're wrong about feeling that you've complicated things.

Thanks for the tips! My question was answered!
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