Sue and I went to our first Sukkot (Feast of Booths or Tabernacles, see post from September 7, 2011) celebration. There were about 80 Russian speaking Jews in attendance. Good food, russian folk music and dancing AND they decorated a sukkot, booth.
The celebration culminated in one of the men waving the lulav and etrog while reciting the customary blessing. Before blessing the sukkot he gave a detailed explanation in both english and russian as to the meaning of the booth. I will confess, I found myself wondering why he was explaining everything in such detail to "Russian Jews"? They were Jewish after all, didn't they already know about the booth, the Lulav and Etrog? Didn't they understand this important celebration of God's provision for His people during the 40 years of wandering in the wilderness?
As he finished I found a coworker and asked, "Why explain to them what they most certainly already know?" and the answer, "They don't have a clue. They are Russian and they are Jewish (in nationalistic heritage) but they are also atheists. Who would have thought you would have to explain a very Jewish ceremony to a bunch of Jewish folks?
Which brings me to the "important lesson". Never, never ever assume what the other person knows or doesn't know. How many "good" people go to the grave without Christ because we just assumed? They went to church, they talked the talk and walked the walk. They carried a Bible, bowed their head before meals, never swore, lived a seemingly moral life...but without knowing Jesus.
Eternity is to important to leave to chance. Unless they tell you they have a personal relationship with Jesus Christ...assume they don't and respond accordingly. Share the Good News someone once shared with you.