For God said: “Honor your father and mother” (Exodus 20:12, Deuteronomy 5:16) and “Whoever speaks evil of his father or mother will be condemned to death” (Exodus 21:17, Leviticus 20:9).
Jesus quotes two clear commandments from Holy Scripture: (Exodus 20:12 / Deuteronomy 5:16) — “Honor your father and mother”, (Exodus 21:17 / Leviticus 20:9) — “Whoever curses his father or mother is worthy of death.” Both of these show how seriously God regards the requirement of respect toward parents. Here “honor” means not only to respect, but also to give honor in spirit, word, and deed, including caring for and supporting them. In the following verses Jesus continues his words and explains why he brings these quotations to mind.