Commentaries:
Behind these Scriptures is a practice whereby people excused themselves from providing for their parents on the grounds of giving offerings (not tithes) to the Temple. On the surface this may seem like an honorable practice, but Jesus condemned them as hypocrites! God wants mercy to people in need, not the "sacrifice" of an offering to God that we think might put us in better standing with Him. That "sacrifice" should have been spent relieving the parent's need!
Jesus quotes Exodus 21:17 as His authority. "Curses" implies afflicting, bringing evil upon, or causing harm or misfortune to. The person who curses a parent, even under the New Covenant, breaks the fifth commandment and is worthy of death. These are sobering words regarding a serious obligation.
John W. Ritenbaugh
The Fifth Commandment (1997)
Notice what Jesus says happened here: The Pharisees had pushed the law of God aside! In the same way, the book of Galatians is not talking about the law of God but about Judaism. The two are not the same thing!
John W. Ritenbaugh
The Covenants, Grace, and Law (Part Twenty-Four)
Other Forerunner Commentary entries containing Matthew 15:5:
Exodus 21:15
Leviticus 20:9
Deuteronomy 21:18-21
Proverbs 19:26
Proverbs 20:20
Proverbs 28:24
Proverbs 30:17
Matthew 23:23
Mark 7:14-23
Luke 11:42