The Hammer of Thunor is one of the most powerful symbols that we have in our spiritual arsenal. Naturally it can be worn as an amulet in order to display our faith to others and also as a magical charm. The axe is closely related to it and indeed of greater antiquity and may be worn as an alternative. See my article : http://celto-germanic.blogspot.co.uk/2013/07/thunors-fiery-axe.html
What is lesser known except to those of us who are involved in esoteric practices is that the Hammer of Thunor may be visualised and used as a spiritual weapon of either defence or offence. To those who are new to the practice of visualisation you may wish to start by carefully drawing a hammer with a red felt tip pen on a piece of stiff white card. Ensure that the hammer is between 6 to 8 inches in height. The hammer should be coloured in, again with a red felt tip pen. Place the card approimately 6 ft away from you as you sit crossed legged on the floor. I find that it helps if this is carried out in the dark with one or two candles for illumination. Try to stare at the hammer for at least 5 minutes with only minimal blinking. The use of a stopwatch will help to determine the passing of time. Then after 5 minutes close your eyes and try to visualise the hammer as accurately as you can. You will find that the image of the hammer is imprinted at the back of the eye. The difficult part is maintaining that image and this is an activity in which you must engage the will, ignoring any kind of external or internal distraction. Attempt to visualise the hammer for at least 5 minutes initially. As you become more accustomed to this practice increase the visualisation time gradually to 10 minutes. After doing this everyday for at least 2 weeks you should then dispense with the card and start to visualise the hammer without any aid or introductory exercises.
I always visualise symbols whether they be the hammer, fylfot or runes in red light, the colour of blood. Essentially we are replicating blood astrally. The colour stands out better than any other when practicing in a darkened room. The visualisation of the hammer will help when setting off to engage in any activity which may have an element of danger. It will also help on a daily basis to increase your self confidence for by doing so you are utilising the power of the Thunder God Himself. Armed with your hammer/axe amulet and your spiritual weapon of visualisation it will help you to face any and all situations.