7:3 wash. The word “wash” is baptizo, normally translated (or really just transliterated) as “baptize.” Whatever is “washed,” or “baptized,” is obviously washed all over, whether the object is a hand, a cup (Mark 7:4) or a person.
7:6 Esaias prophesied. This passage is quoted from Isaiah 29:13.
7:7 doctrines. Those professing believers who reject or distort the Scriptures in order to accommodate some humanistic doctrine (e.g., evolution, uniformitarianism, abortionism) need to study this strong warning from Christ. In context, He was talking about the extra-Biblical humanistic legalism of the Pharisees, but the principle seems applicable to any displacement of Scripture by some human precept.
7:11 Corban. The tradition of “Corban”—that is, “something dedicated to God”—permitted a son to be released from any obligation to care for his parents, thus breaking the fifth commandment. He would claim his possessions belonged to God and were therefore unavailable for other purposes.
7:13 of none effect. This tendency to distort or negate or augment Scripture with one’s own interpretations (or those of others) was not unique to the ancient scribes and Pharisees. God repeatedly warns against tampering with His inspired and now-completed Scriptures (Matthew 5:18; John 10:35; II Peter 3:16; etc.). The last chapter of the Bible strongly warns against adding or taking away any of the words of the Bible (Revelation 22:18-19).