Is praise from Caesar praise indeed?

I don’t find any attribution for it. I think it is just a saying, an aphorism, like “If wishes were horses, beggars would ride.”

Like any other such saying, I imagine it could be used both sarcastically and genuinely, but I don’t think it can be said in the absence of all irony. For example, if the greatest living painter praised your modest exhibit, it might be said to you as a way of noting the extraordinary weight of such praise, but at the same time even the greatest living painter is no Caesar, so it is inflating him a bit as well.

So, in essence I should be careful with how I use it. If I don’t mean it as sarcasm I’ll make sure I clarify.

That seems wise to me. It could sound mocking of the person who paid the compliment.