The most prevalent of all Celtic symbols is the Celtic knot. Found on the high crosses, on jewelry and in the margins of manuscripts, the knot symbolizes how all things in heaven and earth are intricately intertwined and inseparable. The relationship of the members of the Trinity is the prime illustration of interconnection.
Life in this world is intertwined with life in the world beyond this one. The communion of saints was a vibrant reality for the Celts, who believed that those who had died remained present to them. Only a thin, permeable membrane separates those living on earth and those living with God. This was especially true of the risen Christ, whom the Celts believed is not only at God's right hand but also at theirs.
Even though God can be encountered anywhere, there are also certain "thin places" where this happens most easily. Prayer huts were often constructed on these sites, where people could seek silence and solitude.