I do not think, sir, you have any right to command me, merely because you are older than I, or because you have seen more of the world than I have; your claim to superiority depends on the use you have made of your time and experience. ― Charlotte Brontë, Jane Eyre
Why may merely because you are older than I get contained in commas? Does it get utilized like some phrase? May it seem an adverbial phrase? I may get a comma follows that conjunction or.