To suggest a more technical response, based on vows as understood in Hinayana and some Mahayana groups.
Receive the gift into your hand,and acknowledge that you have received it. That completes the act
for the giver. Then you get to perform an act of generosity. You may, for example, say "I wish to
make an offering of this very precious object I have to you." Then you give back the very same
item, saying "it was given to me by a very kind donor, I think you may find it useful and meaningful.
Please receive my generosity at this time."
Sometimes you see Tibetans do this several times with the same thing-- going back and forth a dozen times.
That's a nice image. Kind of the opposite to a ritual that used to occur in my family. My mother would buy shopping for her mother and refuse to accept payment for it, but her mother would refuse to not pay, so the money would go back and forth many times for about 20 minutes, neither party accepting the generosity of the other. This would happen at least once a week, it used to drive me crazy when I was eight!