We usually consider the goats and the sheep being separated in Matthew 25, as "Christians" and "non-Christians". Perhaps that's what it is about. But read that story in context. The whole chapter is about the two types of people coexisting in one group.
The story of the 10 virgins, is a story of young women who are morally pure but some have oil, and some do not, five are wise, and five are foolish. (The beginning of wisdom, is the fear of the Lord. The fool has said in his heart there is no God.) The ones who have oil are taken into the bridegroom's chambers. The others who don't are left behind. They were all in the same group, they were all virgins, they were all waiting for the bridegroom. Yet only 5 were wise and had enough oil. The five foolish were left outside.
The story of the talents (or bags of gold) is a story of three servants. They were each given varying amounts of wealth to care for and invest, by their master. The servant given five bags of gold, went to work and multiplied it. The servant given two bags of gold did the same. The servant given one bag, hid it in the ground and kept it safe, but did no more. All three were servants of the same master, all three were entrusted with talents, all three were expected to accomplish something with what they had been given by the master. The first two heard "Well Done". They probably all expected to hear it. The last though was considered a wicked and lazy servant and was taken away.
Then, toward the end of the chapter the nations of the world are gathered for a final judgment. There is more than one way we can look at "nations" but most often the word nations in the Bible, refers to people groups not necessarily geographical boundaries. Anyway, one gathering of all people groups is brought before the King, notice that all of them call him Lord. From that one 'flock' people are separated into two groups, just like a shepherd will separate his sheep from his goats. Those who are represented by sheep are placed on the right. These are said to be righteous, and blessed of the father. These had served Him well, even down to serving the sick and the poor and the imprisoned. They are given an eternal inheritance. The others though, from that same gathering who were separated to the left 'as goats', are called cursed ones. These didn't regard the poor, the sick or the imprisoned and the King was very offended by their actions. So offended was he, that he says, if you did this to the least of them you have done it unto me.
So, my point? There are two groups of people in the church (I think this is the correct understanding of these parables). You can't necessarily tell them apart by their morality, the way they dress, what they say, or even their claim to serve the Lord. Goats will be right alongside the sheep in the house of God. Yet God knows the difference and He will sort them out. He is the one who will divide his flock into sheep and goats (Not my job). Our job is to be wise (fear the Lord), keep your lamps full of oil (Be filled with His Spirit, not your flesh), be faithful to use what He has given you (Multiply it through diligence!), don't forget the hungry, the poor, the sick, or those in prison but genuinely care for them.
The key to understanding Matthew 25 is found in Matthew 24: 45-51 (Read it). It tells us that the sensible and faithful servant is the one the master can give responsibility to. The others will have their place among the hypocrites. This stirs me to the core! I cannot allow myself to just go through the motions! I must be numbered among the sheep! Can He trust me? Is he REALLY my Lord, or just in name? I am in the group who calls myself a Christian, but am I a sheep or a goat? Wow...