Henry D. Thoreau

It is a proof of a man's fitness for friendship that he is able to do without that which is cheap and passionate. A true friendship is as wise as it is tender.

Henry D. Thoreau

A foe to God was ne'er true friend to man,
Some sinister intent taints all he does.

Young

The silence of a friend commonly amounts to treachery. His not daring to say anything in our behalf implies a tacit censure.

Hazlitt

Think not thy friend one who in fortune's hour
Boasts of his friendship and fraternity.
Him I call friend who sums up all his power
To aid thee in distress and misery.

Saadi