Practically speaking, what do these words of St. Paul mean?
"We are always confident, knowing that, whilst we are at home in the body, we are absent from the Lord:
(For we walk by faith, not by sight:)
We are confident, I say, and willing rather to be absent from the body, and to be present with the Lord."
Here is my take - a distinction between materialism and spirituality:
MATERIALISM:
"To be at home in the body." Constantly looking for satisfaction in eating, drinking, how you look, entertainment. Constantly seeking to please people.
"Absent from the Lord." A state of self-absorption and underlying anxiety, fear of lack, a subliminal fear of what the body can do to you. A state of self-righteousness.
SPIRITUALITY:
"Walk by faith, not by sight." Cultivating trust in that inner sense to guide you, rather than relying entirely upon what you see and hear, etc. Acknowledging God as the source of all good.
"Be absent from the body." To be conscious of the needs of those around you, to love, to seek to do the highest right.
"To be present with the Lord." A state of meekness, knowing that without the higher guidance, you are helpless. A turning to God first, when in trouble. A peace which passes all understanding.
NOTE: It's a process, as per Jesus' parable of the tares and the wheat:
"Mortal
belief (the material sense of life) and immortal Truth
(the spiritual sense) are the tares and the wheat, which
are not united by progress, but separated."
(Science and Health with Key to the Scriptures, Mary Baker Eddy)