The LORD has ordained that HIS people praise HIM. In fact when the Pharisees told HIM to rebuke those who praised HIM, HE said. "I tell you that, if these should hold their peace, the stones would immediately cry out." (Luke 19:40) and also "Yea; have ye never read, Out of the mouth of babes and sucklings thou hast perfected praise?" (Matt 21:16) The message that HE delivered was, that; it was impossible that the sons of GOD should not praise HIM. Praise and worship is the natural result of the work of the SPIRIT of GOD in HIS children as he reveals to them the glory, person, and work of JESUS CHRIST. Religion can teach men to go through the motions of praise, singing of songs, lifting of the hands, etc. but only the SPIRIT can burn the necessity of praise into a man's heart. This is what the LORD meant when he told the woman at the well, "But the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth: for the Father seeketh such to worship him." (John 4:23)
The object of the worship and praise of these multitudes was the ONE they called "the Son of David". Of course we know that they had reference to the LORD JESUS CHRIST. But what is the significance of the title "Son of David"? We must go back to the promise the LORD made to David, (a man after GOD's own heart). David desired to build an earthly temple (house) for the LORD, but he was not allowed to do so. But the LORD, speaking through the prophet, Nathan, told David, "I will set up thy seed after thee, which shall proceed out of thy bowels, and I will establish his kingdom." (2 Sam 7:12) "And thine house and thy kingdom shall be established for ever before thee: thy throne shall be established for ever." (2 Sam 7:16)
David, at the time (and the Jews afterward), considered that the LORD meant that one of David's descendants would sit on a literal throne in Jerusalem forever. In fact Solomon even entertained the notion that he would do so, yet "how art the mighty fallen." The wisest man on earth (the epitome of earthly knowledge) became an idol worshipper along with his heathen wives and ultimately succumbed to the same death as all sinful flesh. Then after a few years, the grand temple that Solomon built was destroyed and its riches carried away to Babylon. Some of its glory was restored in the days of Nehemiah but the nation of Israel was once again conquered and was living in servitude under the Roman Empire when this triumphal entry was made by the LORD JESUS CHRIST. Yet there remained in the minds of the Jews that promise which was given concerning the throne of David and they believed a messiah or savior would come and recapture that throne and unite and restore the kingdom of Israel to its former glory. No earthly power could have taught these people that this carpenter from Nazareth was indeed the true "Son of David" which would sit upon the throne of HIS kingdom forever. Yet here they are casting palm fronds and flowers in HIS path and shouting and singing HIS praise. GOD is able to enlighten men without the aid of others, HE is able to awaken them out spiritual darkness whenever and however HE chooses. The LORD made them aware of HIS ministry and teaching in the days before this but HE chose to have them bear witness to HIS Kingship on this day.
Now these Jews along with the LORD's own disciples were convinced that the one who was the "Son of David" would surely rise up against their Roman oppressors and set them free as he once again occupied an earthly throne. None of them had any understanding of the true nature of the freedom and deliverance that HE came to establish nor did they understand that HIS kingdom is not of this earth and has no literal throne in the city of Jerusalem. If the kingdom which CHRIST came to establish is one of flesh and blood then the promise which HE gave to David many years before would have been broken because the LORD said "the kingdom would be established forever, but for over 400 years no one sat on that throne. The reality is that when the promise was given to David it was a promise that the Eternal KING would occupy the throne of a kingdom which would never pass away. Just as the promise made to Abraham's seed was not to his seed as many but as ONE, even JESUS CHRIST. (see Gal.3-16-18). There are still a multitude even in the present day who are convinced (mistakenly) that there is going to be a reestablishing of the "Kingdom" of Israel in a literal fleshly sense. The kingdom of the LORD JESUS CHRIST has never changed from its inception (eternity past) throughout its continual reign and will not change in the future. JESUS CHRIST is the fulfillment of all prophecies and the revelation of all mysteries which the LORD of GLORY intends for men know.
"As the "son of David", the LORD JESUS has established HIS kingdom totally without any aid from men. (see Ps.2:1-12) As the "son of David" HE has become both the apple of HIS FATHER's eye as well as the hope and desire of the true "Israel" of GOD. (see II Sam. 23:5; Ps.73;25) As the "son of David" he meekly entered Jerusalem seated upon an ass, befitting a King of Israel, but when HE returns it wll be upon a white horse, befitting the KING of glory, in flaming fire taking vengeance on them that know not GOD. (see Rev.6:2; 19:11; II Thes.1:8)
"For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counsellor, The mighty God, The everlasting Father, The Prince of Peace. Of the increase of his government and peace there shall be no end, upon the throne of David, and upon his kingdom, to order it, and to establish it with judgment and with justice from henceforth even for ever. The zeal of the LORD of hosts will perform this." (Isaiah 9:6-7)mam