After a casual reading of the sheep and goats (Matthew 25:31-46), these verses "on the surface" seem to suggest that salvation is the result of good works. *All Scripture proves itself right and non-contradictory when compared with the totality of Scripture. This passage has to be taken alongside the whole of Scripture.
Jesus was not advocating salvation by works. That would be contrary to Romans 4:4-6; Ephesians 2:8,9; 2 Timothy 1:9; Titus 3:5 etc... One's works are an effect of (and therefore indication of) one's salvation status, rather than being a cause of one's salvation. This is not performance based salvation, but salvation based performance. The good deeds mentioned in Matthew 25:35-36 are merely the fruit that will be manifest in the lives of the redeemed.
Those who are placed at Christ's right hand are not there based on the merits of their good deeds, but because Christ imputed His righteousness to them (Romans 4:2-6; Philippians 3:9). When works are mentioned in connection with salvation, the works are always the result of, not the condition of, receiving salvation. The stress is on works as a manifestation of one's faith (or lack thereof), not simply on the faith from which these works follow. So it is understandable that in this context, Matthew would stress the works that are a manifestation of "faith by which one receives eternal life."
Notice how love for other Christians is an indication of one's salvation status: 1 John 3:10 - In this the children of God and the children of the devil are manifest: Whoever does not practice righteousness is not of God, nor is he who does not love his brother. He who practices righteousness and loves his brother does so BECAUSE he is "of God" not to become of God. 1 John 3:14 - We know that we have (past tense) passed from death to life, because we love the brethren (present tense). Loving the brethren is the result of, not the condition of passing from death to life.
