"The triumphal entry cannot be separated from the crucifixion, even as the latter can't be separated from the resurrection. Jesus was deliberately coming up to Jerusalem to give his life as a random for the sins of mankind; it was God's will that the sacrifice should be made in such a public manner that the attention of the world and of the ages should be concentrated upon it."
R. C. Foster
Foster, R. C. Studies In The Life Of Christ. College Press. 1979.