1. What does this "cheer" mean? "good spirit" or "the sacrament"?
2. Does this "which" refer to "shelter" or "abiding source"?

st57)Man differs from the lower animals because he preserves his past experiences...But man lives in a world where each occurrence is charged with echoes and reminiscences of what has gone before, where each event is a reminder of other things. Hence he lives not, like the beasts of the field, in a world of merely physical things, but in a world of signs and symbols..A flame is not merely something which warms or burns, but is a symbol of the enduring life of the household, of the abiding source of cheer, nourishment and shelter to which man returns from his casual wanderings.