It is instead about how the nations treat those who belong to Christ. In stating “These brothers of mine” Jesus identifies those who are aided or ignored as believers. Calvin in his commentary on the Gospels points out that this text begins with an understanding that the righteous have their salvation from somewhere else besides themselves. Calvin writes:
But before speaking of the reward of good works, he points out, in passing, that the commencement of salvation flows from a higher source; for by calling them blessed of the Father, he reminds them, that their salvation proceeded from the undeserved favor of God.With some explanation from the Old Testament Calvin adds:
There can be no doubt, therefore, that Christ, in describing the salvation of the godly, begins with the undeserved love of God, by which those who, under the guidance of the Spirit in this life, aim at righteousness, were predestined to life.And Calvin points out that in his day there were some who used this text to suggest that visiting the sick, the prisoner, giving food, drink and clothing to the needy was all that was required of a Christian. Almost prophetically he wrote , “Most improperly, therefore, do fanatics, under the pretext of this passage, withdraw from hearing the word, and from observing the Holy Supper, and from other spiritual exercises; for with equal plausibility might they set aside faith, and bearing the cross, and prayer, and chastity.”
R.T. France in the Tyndale Commentary brings further clarity noting that Jesus deals with judgment throughout chapters 23-25. France also points out that recent scholarship sees judgment coming against those who have rejected Christ’s brothers (the adopted children of God) who have proclaimed the gospel. Rather than philanthropy, it is “men’s response to the kingdom of heaven as it is presented to them in the person of Jesus’ ‘brothers.’ It is therefore, as in 7:21-23, ultimately a question of their relationship to Jesus himself.”
France likens the sufferings of “the least of these my brethren” to the sufferings of Matthew chapter 10 and to Paul’s list of hard experiences in 2 Corinthians 11:23-27.” Those who belong to Jesus have not understood that by receiving those who proclaimed the gospel to them and others, via their care, they have ministered to Jesus. Those who have rejected the brothers and sisters of Christ and their message of salvation show their rejection by ignoring their needs.
I remember many years ago reading a story of a pastor, in the now dismembered USSR, who was in prison for his faith. His wife was destitute and spent many nights alone on the streets even in the rain. She was one of the “least of these.” As France puts it:
It is in any brother of Jesus, however insignificant, that Jesus himself is served, and it is that service which is therefore the criterion of judgment, as it indicates how one responds to Jesus himself. It is important to note that, in each of the passages which refer to ‘these little ones’, the point is to declare the importance of such people because of their identification with Jesus (see esp. 10:40, 42, 18:5).And whoever receives one such child in my name receives me; but whoever causes one of these little ones who believe in me to stumble, it would be better for him to have a millstone hung around his neck, and to be drowned in the depth of the sea.(Matthew 18:5-6)