Charles Ellicott Commentary Matthew 19:18

"He saith unto him, Which? And Jesus said, Thou shalt not kill, Thou shalt not commit adultery, Thou shalt not steal, Thou shalt not bear false witness," — Matthew 19:18 (ASV)

He said to him, "Which?"—Literally, of what kind? The questioner had been trained in the language of the schools and had heard debates about which was the great commandment of the Law (Matthew 22:36). He was asking which class of commandments he should keep in order to obtain eternal life.

Thou shalt do no murder—Our Lord’s answer was clearly determined by the method we previously mentioned, which is reminiscent of Socrates' approach. To a questioner with a different character, He would have pointed to the two great commandments on which all the Law and the Prophets hang: the love of God and the love of man.

Here, however, it was more in harmony with His loving purpose to set aside the commandments of the first table, which tell people of their duty toward God. Instead, He directed attention only to those that speak of our duty to our neighbor, as these were considered common and familiar matters.

The change in the order of the commandments, where the fifth now follows those it precedes in the Decalogue, seems to suggest a deliberate design. The intent was to lead the questioner from the negative to the positive forms of the law—from definite prohibitions of specific acts to the commandments that are “exceeding broad,” fulfilled only in the boundless realm of the heart's affections.