What does the lost coin represent in the parable of the lost coin?
The lost coin represents the nation of Israel, which was God's by covenant promises but became lost. The lost one is whom He seeks and brings to Himself, just as He did the little lost sheep. It is not an individual Gentile.
Les explains that in the parable of the lost coin, the coin should be understood as the condition of the nation of Israel, that which was God's by covenant promises. He points out that God deals with Israel on two levels, national and personal. Nationally, Israel is blind, but individuals can still be saved. The lost coin, like the lost sheep, represents the lost one whom He goes and brings to Himself. So the lost coin represents Israel's national lost condition under the covenants, not an individual Gentile.