Odin is a multi-faceted God. As the Allfather (Alföðr) we should expect nothing less. Not only is he ruler of Asgard, but he is all things to all humankind and in many ways we are a reflection of his complexity. Many can see traits of Odin in themselves and this is why many are drawn to him.
The Trinity knot is also called the Triquetra and is one of the best known symbols in Celtic culture. The Celtic Christian church used it to represent the Holy Trinity, but other cultures used the symbol too and each attached its own meaning to it.