" T-4.II.6. Only those who have a real and lasting
sense of abundance can be truly charitable. This is
obvious when you consider what is involved. To
the ego, to give anything implies that you will
have to do without it. When you associate giving
with sacrifice, you give only because you believe
that you are somehow getting something better,
and can therefore do without the thing you give.
“Giving to get” is an inescapable law of the ego, which always evaluates itself in relation to other egos. It is therefore continually preoccupied with the belief in scarcity that gave rise to it. Its whole perception of other egos as real is only an attempt to convince itself that it is real. “Self-esteem” in ego terms means nothing more than that the ego has deluded itself into accepting its reality, and is therefore temporarily less predatory. This “self-esteem” is always vulnerable to stress, a term which refers to any perceived threat to the ego’s existence. "

― , A course in miracles: Text, Vol. 1