N 4 different instances, parts of the Old Testament are quoted in this chapter (vs. 5, 13, 16 & 42). It is evident then that Matthew was adding more evidence backing his claim that Jesus of Nazareth was indeed the Messiah of God and the rightful King of Israel.
Chronologically, Jesus was nearly at the end of His earthly ministry. The event recorded at the outset of this chapter is commonly called the "Triumphal Entry" and in our culture is celebrated annually on "Palm Sunday," the week before Easter. Christ's entry – riding on a donkey into Jerusalem (to a very enthusiastic reception from a large crowd of Jews) – should draw our attention to the future, when He will come again. The next time He enters Jerusalem, He will come as a conqueror.
Jesus' power to conquer was demonstrated when He cursed the fig tree and caused it to immediately wither and die. Additionally, Jesus' right to conquer was communicated by His action right after His triumphant entry. He went into the temple and cleaned house. He threw out the crooks. This bold action elicited 2 very different reactions from 2 very different groups of people. The young people in Jerusalem worshipped Him vigorously (vs. 15). The religious leaders were upset and cynical.
Jesus did not even dignify the criticism of the scribes and Pharisees with a response. Instead, He began to interrogate them concerning their rebellious response to John the Baptist. Since the religious leaders didn't believe or respect John's ministry, they were not prepared to follow Christ when He began to exercise His authority over them. They had rejected this Cornerstone (vs. 42). In other words, although Jesus was the chosen one of God, these religious Jews refused to include Him in their futile efforts to build a spiritual house. Regardless, Jehovah had elected to build with His Son as the foundation.