14 Jesus got a young donkey and rode it, just as the Scripture has it: 15 No fear, Daughter Zion: See how your king comes, riding a donkey's colt. 16 The disciples didn't notice the fulfillment of many Scriptures at the time, but after Jesus was glorified, they remembered that what was written about him matched what was done to him.
Matthew Henry's Commentary on John 12:14-16
Commentary on John 12:12-19
(Read John 12:12-19)
Christ's riding in triumph to Jerusalem is recorded by all the evangelists. Many excellent things, both in the word and providence of God, disciples do not understand at their first acquaintance with the things of God. The right understanding of spiritual nature of Christ's kingdom, prevents our misapplying the Scriptures which speak of it.