Be courteous to all, but intimate with few, and let those few be well tried before you give them your confidence. True friendship is a plant of slow growth, and must undergo and withstand the shocks of adversity before it is entitled to the appellation.
~ George Washington [Letter, Jan. 15, 1783]
Finally, be ye all of one mind, having compassion one of another, love as brethren, be pitiful, be courteous:
~ 1 Peter: 3 vs. 8 (Bible, KJV)