John Calvin Commentary Luke 10:29

"But he, desiring to justify himself, said unto Jesus, And who is my neighbor?" — Luke 10:29 (ASV)

But he wanting to justify himself. This question might appear to be of no importance for justifying a man. But if we recall what was previously stated, that men's hypocrisy is easily detected by means of the second table—for while they pretend to be eminent worshippers of God, they openly violate charity towards their neighbors—it will be easy to infer from this that the Pharisee practiced this evasion so that, concealed under a false mask of holiness, he might not be brought into the light.

So then, aware that the test of charity would prove unfavorable to him, he seeks concealment under the word neighbor, so that he might not be discovered to be a transgressor of the Law.

But we have already seen that on this subject the Law was corrupted by the scribes, because they considered none to be their neighbors but those who were worthy of it. For this reason also, this principle was accepted among them: that we have a right to hate our enemies, (Matthew 5:43). For the only method to which hypocrites can resort to avoid self-condemnation is to turn away as much as they are able, so that their life may not be tried by the judgment of the Law.