"As we need the Gods and Goddesses in their many forms of energy, so do the Gods and Goddesses need us." Both Celts & Wiccans believe that we can tap into that stored power source and use it.
Both Celts & Wiccans respect other religions & do not believe that all other religions are bogus. They believe that religions simply use different methods to achieve the same ends. They honor all religions and scoff at none.
First let me say, that I use the word "they" instead of "I" or "We" because obviously, we are speaking of 2 different religions here. And although they have been combined in modern day "Celtic Wicca", they are not one & the same. I prefer to tell you of these religions without bias, thus using third person instead of first.
Wiccan Rede Explained
Wiccans: believe in the Wiccan Rede, "An’ it harm none, do as ye will." They do not see this as a solid vow however, but as a permissive one. As long as an action harms none, then they feel that they are free to employ it. However, should an action bring harm, then responsibility and consequences must be faced.
Now some think that this rede is a direction against all violence and aggression. This is not true. "An it harm none" says it all if you just think about it. None is meant to include yourself as well. If someone subjects you to an act of violence, then you have every right to turn those forces back on him or her. Being Wiccan gives you no rights as a wimp, by any means. Do not use it as an excuse for letting someone get away with murder. Wiccans do however believe in a passive aggression if this can be done. That is to say, they reflect the evil back to the source and turn his/her own aggression against them. If someone violates your rights, you have every reason to turn this back on them and violate theirs. One major point here is this however. You do not initiate a slug fest just because someone uses harsh words against you. Use suitable force to the crime. An eye for an eye, more or less. If someone murders someone close to you, then they do indeed owe you a blood oath to be taken as you see fit. If that means a life, then so be it as far as the requirements of the Rede go. You're off the hook here. Don't have to worry about the threefold law. Of course, you can also go to jail for this, so be prepared to face the consequences. Death is never a first option. It should only be done in self-defense or as a means to an end of violence. (The Rede is written in complete context under the Priciples section.)
Wiccan Three-Fold Law Explained
Now as for consequences, as I mentioned, Wiccans believe in the Three-Fold Law. They believe that ones' actions are repaid times three. Hence, if a Wiccan knowingly harms another without just cause, then they will be repaid for this act of disobedience threefold... is what this law is saying. Naturally whatever you do has consequences in this life and only the truly ignorant would think otherwise. Magick has absolutely nothing to do with this. Even the critics of the ancient religions will concede that if they rob a bank then they might, sooner or later, be arrested. This is but common sense, I think.
Wiccans do however believe that all things will be paid back in threes at some time or other. This seems to vary upon the Tribe of Wiccans that one speaks to. Alternately they believe that if you commit an act of kindness or goodwill, that act will also be repaid to you threefold. "What ye sow, so shall ye reap."
Celt "Rede" Explained
The Celts, on the other hand do not follow the Wiccan rede at all. It may be hard for you to understand this, because you might think that without the rede that the Celts could deal in whatever they pleased without fearing the consequences. This doesn't hold true, however, due to the fact that the Celtic Principles and Beliefs hold: Honor, Courage, Truth, Strength, Wisdom, and Eloquence, & the "spoken word, in the highest esteem possible. This is their "Rede", so to speak. Honor above all, so you might consider what "Honor" constitutes. I am more of the Celt persuasion (oh yes, truly pagan.) than Wiccan for I was raised on these values & they are as dear to me as my life. I believe in "Justice for all" as well. Celts generally do not fear the three-fold law for they don't believe that good or bad simply "bounces" back at you on some later date. Cause & effect, yes, but if justice was due, then once justice is accomplished, the world is once more in balance. No bouncing! And no repercussions in another lifetime either. There is little discussion due the Laws of the Celt practitioner because they simply do not have any. Honor above all is the only way for the Celts of Olde and for most of today's practitioners as well.