Within Heathenry you will see a wide range of approaches and beliefs, from those who don't believe in the Gods at all, to those who see them as archetypes, to those who believe the Gods exist as unique individual beings. In the same way you will see a range of approaches to how we relate to the Gods. At one end there are people who only acknowledge the Gods in ritual, while at the other are those who feel they have a special connection to one particular deity; most people likely fall into the middle of that spectrum. A person who feels especially close to one deity may refer to that deity as their fulltrui (for a God) or fulltrua (for a Goddess) which means, roughly, "trusted friend", and may refer to themselves as a man or woman of that deity - as in Thorsman or Freyswoman. Not everyone approves of the idea of such devotion to a deity and conversely many people mistakenly see it as necessary or required so I thought it would be helpful to discuss what it really is in a historic and modern context. The following is, as always, my own opinions and views on the subject. As someone who considers Odin her fulltrui much of my viewpoint is shaped by my own experiences and understanding of the subject, although my choice to equate fulltrui and dedication may not be shared by everyone. I feel though that having a "trusted friend" among the Gods requires a relationship of dedication to that deity; its also the best verb I can find to describe the action of being fulltrui.
First off lets clear up one of the most common errors, that this idea is entirely modern and a hold over from monotheism. Although that argument is a common one against dedication, the idea of being dedicated to a God within a polytheistic Heathen context does have a historic basis. Many people try to argue against the entire idea of being fulltrui with a deity by attacking its authenticity as a Heathen practice, but there is enough evidence of people during the Heathen period who were dedicated to a specific deity to make the concept credible, although not common. We know that there were priests and priestesses dedicated to specific deities, such as the priestess of Frey who traveled the land with an effigy of the God in a wagon (Heinrichs, nd). and possibly the priest who served the shrine of Nerthus which Tacitus discusses in Germania. We also see more ordinary people, if such can be found in the Sagas, who were believed to be especially close friends of a certain God and would take that God's name as part of their own. We also know that it was not simply a matter of a person choosing to focus on one deity, but rather that the deity also seemed to be a "friend" to the person in return. In Eyrbyggja Saga Thorolfr Mosturskeggi who was known as a friend of Thor, a feeling that appears to be mutual as the story calls Thor the astvinr (beloved friend) of Thorolfr (the Troth, 2006). When making landfall in Iceland Thorolfr trusted Thor to guide him to the best place to settle and build his new home by tossing his Thor pillars overboard and following where they landed. Thorgrim Freyrsgothi in Gisla Saga was said to be so loved by Frey that the God would not allow snow to cover Thorgrim's grave.Within mythology even we can find examples of those particularly favored by a certain deity - Odin was known for this, although his favor might end in a bloody battle death - and we know that there were those who offered excessively to one deity to gain that favor, such as we see in the story of Ottar and Freya. So from this we can see historic evidence of both priests and priestesses of one specific deity and also non-clergy who were considered close friends of a specific deity.
Now that we have established the precedent, lets look at modern fulltrui. The idea itself is fraught with confusion, both by people who aren't familiar with it and people who should be, and often this confusion is used to try to either dissuade or encourage the practice, which naturally creates more confusion. So I am going to try to discuss some of the most common things I hear and the reality of dedication.
Someone who is fulltrui with a deity is still a polytheist. Being close to one particular deity does not mean that other deities are not acknowledged or honored, or that the person is actually a monotheist. I am fulltrui with Odin and also regularly honor other Heathen Gods. Having a close connection with one deity in no way detracts from or lessens the honoring of other deities as well. Hand in hand with that, being fulltrui with a deity is not a way to cling to monotheism - I have never been a monotheist and have nothing of that to cling to, for one thing, and for another I have never met anyone who was dedicated to a deity who felt that their deity was the only or ultimate deity. I may be dedicated to Odin but I blot to many other Aesir and Vanir as well, and regularly acknowledge a combination of Gods. I pray for healing to Odin, but also to Eir. I honor Sunna with Sigdrifa's prayer each day. I offer to Frigga, Freya, Frey, Thor, Njordh and Idunna during the year, and regularly offer to the landvaettir and my ancestors. Being fulltrui with one deity does not limit my honoring of others. Think of it as you would human friendship; even when you have one special close friend you still have at least a few other friends that you also spend time with and talk to.
Someone who is fulltrui with a deity does not think they have a magic phone line to that deity or that the deity is involved in every tiny aspect of their lives, or at least I have only rarely encountered that mindset. There will always be some who believe that their God sends them messages in their cornflakes, or that they must consult their God about what color socks to wear, but the majority of people who are dedicated to a specific deity do not think that their deity cares about the minutia of their life. There may be a sense or feeling of closer connection to that deity compared to other deities, there may be a belief in communication with that deity, especially by those like myself inclined to seidhrwork or who are particularly spiritual, but it is generally perceived as coming in dreams or in trances or altered states. Some people may indeed receive more direct communication more often, but they won't be the ones bragging about it to anyone who will listen or using it to try to prove that they are special. There is a difference between someone who is a mystic and someone who is being overly superstitious or seeking attention. I would never deny that modern people do encounter and communicate with the Gods, and people who focus more on a specific deity may experience this more often, but the idea that someone who is fulltrui with a deity has a direct line to that deity that other people don't is not accurate. We all have that connection to the Gods we honor, whether we acknowledge it or not. Omens, of course, in a wider sense are believed in by many and would not fall into this context; for example I don't know anyone who wouldn't see thunder during a Thor blot as a positive sign.
Someone who is fulltrui may feel that they serve the deity they are dedicated to or they may not. I know people who simply accept that there is a special connection there and honor that with extra focus on that deity and more offerings, and I know others who serve their fulltrui in a capacity closer to that of a priest
or priestess. As with human relationships no two are ever exactly the same, and that's a good thing. Some people formalize the relationship with an oath and others simply fall into it over time, without any official agreement. For those like me who do feel called to serve, the direction of that service may manifest as a feeling or intuition that certain things are wanted - I began studying seidhr for this reason and also began teaching rune classes from the same subtle feeling, and I got a valknot tattoo after being instructed to do so in a dream; divination can be used to verify or disprove these feelings. The person might also serve by doing things that they feel will honor their fulltrui or can be seen as a type of offering - I have ravens tattooed on my body as a voluntary offering to Odin, for example. In ancient times a person would have become a priest or priestess in a temple or shrine (as in Upsalla or Tacitus's account in Germania) or may have traveled with an effigy of the God, as in the story of Frey's priestess. In modern times this service takes a different form, although I do know one Freyaswoman who serves by maintaining a traveling shrine to Freya at various events.
Being fulltrui with a deity is not a requirement of Heathenry, nor is it necessarily the norm. The idea that all new Heathens need to find a patron deity to dedicate to is something that is increasingly common and totally superfluous. Modern Heathenry, as a religion, is not based on this idea at all, and in fact for a new Heathen such a focus could have a negative impact on building a feeling of connection with all the Gods in general. Dedication should be an organic process which occurs over time based in mutual responsiveness, not a quest to meet an imagined goal. Quite frankly, since deeper dedication to a deity can prove extremely challenging, I honestly don't know why anyone would seek it out. Ottar offered to Freya to gain a boon from her, and she turned him into a boar and rode him into Helheim to get what he sought. Odin's favored people tended to die in battle in the Sagas to earn their way into his hall as einherjar. Everything has a cost balancing out the benefit.
Along with that last idea; although it does happen that a person comes to the religion through one God or Goddess, that singular connection should not get in the way of the wider connection nurtured by a polytheistic approach. Some people who are fulltrui with a deity mistakenly feel that all of their loyalty should be focused on that deity, and may even feel guilty for acknowledging or honoring others, but that idea, I think, is foreign to Heathenry. In other words, just because you may feel that Njord led you to find Heathenry doesn't mean you should only ever blot to him. Honoring the Gods is intended to nurture reciprocity with them, and in order for this to create balance and blessing in our lives we must honor different deities who offer blessings in certain aspects of our life. Although having a fulltrui does mean going to that deity more often and for many different things it doesn't negate the wider benefits of having many Gods to offer to or call on.
Dedication is also not something to be taken lightly. One should never jump into dedication, both because oaths are a very serious matter and because it is, generally, a permanent relationship. If you dedicate to Odin you must be willing to give your life to him, or you should not do it. While occasionally a deity may release a person from dedication its important to remember that in many ways it is not up to us, so we should never assume we can change our minds if we find out we don't like the experience. The Gods are real beings and what is offered, if accepted, is not ours to take back, any more than we can take back mead poured out on an altar. In the same way as Odin offered himself to himself on the Tree, I made myself an offering to Odin; not all offerings are accepted - mine was. It cannot be taken back, or undone. Remember that the entire idea of fulltrui is that it goes both ways; we are friends to that God and that God is a friend to us. We have free will and can choose not to nurture that friendship, just as the deity may not accept our friendship, but once the bond is forged, particularly if oaths are involved, it cannot easily be broken.
Which leads us to the final point; dedicating to a deity is not a matter of deciding that you really like one particular God or Goddess. It also - I hope obviously - is not about wanting to impress or intimidate people. Many people seem to feel that if they really admire or relate to a specific deity then they should dedicate to that deity, but the reality is dedication is in many ways a calling. Not only must we be willing to dedicate ourselves to that deity but the deity must want and accept our dedication. And sometimes - maybe most times - the deity who calls us will not be the one we expect or would have chosen ourselves. I am very fond of Heimdall and felt a special connection to who he is and what he represents, yet it was Odin who called me - not who I would have expected or chosen for myself. Being fulltrui with a deity is more than just really liking that God or Goddess; its about feeling that the deity is responsive to you and being willing to repay that responsiveness.
Dedication is a modern concept rooted in past practices. It is something that can be very fulfilling but also very challenging, as reciprocity requires that as much be given as is received. It is a personal connection that exist between an individual and a deity, and in most ways it is significant only to the individual. It does not make you special or a better Heathen, just as not having a fulltrui isn't better or more genuine. Being fulltrui is about putting your trust in a deity, and having that deity respond as your astvinr, a beloved friend; it is about that special connection which is forged with time and commitment, rather than whim.
Heinrichs, A., (nd). The Search for Identity: A Problem after the conversion
the Troth (2006). Our Troth, volume 1