Dreams or visions about the altar tell you that you are looking for support, help from the afterlife, the spiritual and the greater purpose. Another explanation is to be connected to a partner, work, family, friends and especially to spirituality and justice; it also stands for the infinite in our cooperation.
Another explanation is that there is a chance of new friendships and relationships and connections. It could be that a good time is coming with a lot of new unknown possibilities and inner or spiritual growth. Pay attention to what you have on the altar these objects are a deeper signal about which the dream is about.
Laying out, decorating an Altar stands for connecting with your pure self, your soul and the hereafter, but above all wanting to make the connection with your deceased loved one.
The desire for support and being heard, praying and manifesting and visualizing; the power of thought power and the spiritual connection to your higher self, the universe and co-creation. With this kind of dreams always pay attention to the colors and materials you use, this tells more about the underlying messages and life lessons, soul answers etc.
Are you dreaming of a witch altar then it tells you that you have already found the knowledge and wisdom you need at this moment in your life. An alternative explanation is that you still have to match all information or knowledge and / or make it known to yourself, but you can also think of working out and applying it.
Another explanation is that you find a balance between your male and female energy. In addition, a witch altar can be experienced both positively and negatively, depending on how you feel about magic and nature religions.