Different pantheons ...

[Elaethril]

I am beginning to feel called to specific deities in my worship. Since I've never had this particular experience before and I know very little about it, I'm curious if it matters if they (technically) belong to different pantheons (one from the celtic pantheon, the other Roman).

(My worship in the past has always been to the Lord and Lady, God and Goddess rather than a specific deity.)

[Arion]

I don't think it really matters. Plenty of people will use gods like Cernunnos and Diana, for example, in the same ritual. As long as the 2 dieties mesh well together, its fine, just give it a shot and see how things go. The Celtic and Roman pantheons aren't -too- different from each other, so i think you're okay. It can also depends on the type of diety. Two war gods of different pantheons might not work so well together, for example.

[Morgandria]

No, it doesn't matter, as long as you are not calling gods from different pantheons together in the same ritual. It's more respectful if you call your god
or goddess with an appropriate consort from the same pantheon as them.

[Toby Stimpson]

I agree with Purplepanther...although I might add that it is worth looking at the two traditions the two deities are from and merging them in that one ritual. :)

Namaste

Tobias

[Meadhbh]

Celtic & Roman. For the most part I would say no on that. Its never a sure thing when you mix pantheons, even when the cultures can mesh together fairly easily. That would not be the case here. If you want to work with different pantheon's thats your choice, but I won't advise you to work with them in the same ritual.