Families are very important to God. The Bible says that every family derives its special qualities from Father God Himself (Ephesians 3:15).  So, when Jesus apparently ignores His mother and brothers, what is going on?  Is He disobeying the 5th Commandment?  In one sense, parental honour has to do with their authority being "in loco Deo" (in place of God) ... a child needs parents who will faithfully instil truth and teach the child how to reject error.  They are God's appointed trustees of the children; His agents of truth and love.  Their parental authority comes from Him.  That is why it is important to honour our parents (Deuteronomy 5:16; Matthew 15:4; Ephesians 6:1-3).

However, with Jesus, the command chain worked the other way.  Although the human body of Jesus was first grown in Mary's womb (Luke 1:35), His conception was not the start of His existence (Colossians 1:16-17).  He had always existed with the Father and Holy Spirit.  His was the authoritative Word which created the world and human beings in the image of God (John 1:1-3).  His continues to be the Word which sustains the universe and holds all matter together (Hebrews 1:3).  Jesus' incarnation was necessary for the work of salvation, in which He became the Lamb of God sacrificed for the sins of the world.  In order for God to suffer the death sentence due to each of us, He needed a human body: God cannot die but human beings can (Hebrews 10:5).  That was the purpose of His birth, life and death (Colossians 1:19-20).  

As a man, Jesus submitted Himself to Father God (John 14:31).  He had a higher authority than Mary.  However good Mary may have been, she was wrong to assume it was her responsibility to rescue her boy from His 'delusions' (Mark 3:20-21).  However, Jesus was gentle and did not publicly rebuke His mother and half-brothers – although they did not understand Jesus’ mission (John 7:2-6). Instead He told the crowd that His family was much bigger than the household in Nazareth.  Jesus' true family is all who are born again by His Spirit (John 3:3-7), and obey what He says (1 Peter 1:2).

The true family of Jesus are still marked out by their willingness to do what God wants (John 15:14).  Although God's Will should be faithfully transmitted by our parents (Deuteronomy 6:6-7) - they must not make it up and cannot define what is true. It is Jesus who has the right to do that (John 14:6).  While we have a duty of honour to our parents (Exodus 20:12; Mark 7:10), as gospel-believers we have a higher duty to obey the gospel of our Lord Jesus Christ (2 Corinthians 9:13;  2 Thessalonians 1:8).  Where obligations conflict, it is the Word of God, voice of Jesus, that is in control of the situation.  Hebrews 4:12-13 says, "For the word of God is alive and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart. Nothing in all creation is hidden from God's sight. Everything is uncovered and laid bare before the eyes of him to whom we must give account."  We, as children and parents along with every human being, are ultimately accountable to Him.