I have a few questions, I hope you don't mind. In East Asian countries, it is customary to bow to elders and those older than you. Is this not allowed? Also, it is customary to bow to ancestors who've passed away at their graves. Is this not allowed as well?
In your region bowing is a sign of respect. In the Old Testament, older people were to be treated with respect. "You shall rise before the gray headed and honor the presence of an old man, and fear your God: I am the LORD" (Leviticus 19:32). In their culture one stood. In your culture you bow.
The graves of those who died only contain the remains of their mortal bodies. The people are not there. If the bow is merely a sign of respect to their memory, that is not a problem. If it seen as attempting to incur the favor of those who have died, that would be wrong because the dead are no longer involved in life. "For the living know that they will die; but the dead know nothing, and they have no more reward, for the memory of them is forgotten" (Ecclesiastes 9:8). They cannot come back to this world. "So man lies down and does not rise. Till the heavens are no more, they will not awake nor be roused from their sleep" (Job 14:12).
Oh, I see. I understand now. Thank you!