For instance "goodbye" is said to arise from the archaic, " God be with ye " and is more likely connected with the " bye and bye' which means " some time again " , which I find more satisfying in that they will find they are surrounded with goodness until we meet again.
It meets the likeness of " farewell " or " fare thee well " that implies leaving, but in do and now it's in dictation mode so what we have to be as careful about what we saying so that "wellness be your fare", a blessing that follows you where ever you go, your fare abundant.
And goodbye is sister to " au revoir " that recognizes that we will see one another or re-see one another again in the bye and bye. It means " Adieu, in French also that DIeu follow you or in Spanish Adios, That Dios follow you as you leave.
Each phrase imparts sentiment and good will that is expansed to one another and more than you think. Be careful what you say. Language counts.
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