The two parables that precede this one (Parable of the Ten Virgins and the Parable of the Talents) stress waiting for and preparing for the return of Christ. "This parable is similar to the Rich man and Lazarus in that the time to repent and be converted, the time to care for the poor on one's doorstep, is past."McKenzie, Alyce. "Judging Sheep and Goats: Reflections on Matthew 25:31-46", November 14, 2011 It also recalls the parable of the Good Samaritan. As associate professor of Biblical Languages at Union Presbyterian Seminary, E. Carson Brisson, says, "Let it be noted that this list of afflicted and needy individuals is, at first glance, a list of the very ones who appear to be bereft of God's favor. These are ‘the least.’ These are truly ‘other.’"Brisson, E Carson. "Matthew 25:14-30." Interpretation 56.3 (2002): 307-310. ATLA Religion Database with ATLASerials. Web. 5 Sept. 2013. Also, see Ezekiel 34:4 for a similar list of afflicted and needy individuals whom God favors. This pericope is also similar to the Parable of the Wheat and Weeds which will be sorted out on Judgment Day. What distinguishes the sheep from the goats is the acceptance or rejection of Jesus' message.
