Why does Gandalf have the third elf ring?

[Frodo Baggins]

This is why Cirdan gave Narya to Gandalf. it says that Cirdan saw deeper than any other in Middle-earth and knew who Gandalf was and where he came from and where he was going. (i.e. Olorin wisest of all Maia)


' "Take this ring, Master" he said, "for your labours will be heavy; but it will support you in the weariness that you have taken upon yourself. For this is the Ring of Fire and with it you may rekindle hearts in a world that grows chill. But as for me, my heart is with the Sea, and I will dwell by the grey shores until the last ship sails. I will awit you." '

Check the Appendicies, the tale of years, the Thrid Age.