The song by 12 year old M Styles, is in relation to the religious day known as Palm Sunday that occurred one week prior to the resurrection of Jesus and the Sunday prior to His Friday crucifixion. It is shared in all four Gospels (Matthew 21:1-17; Mark 11:1-11; Luke 19:29-40; John 12:12-19) as one of the key events of Jesus' earthly ministry.
Jesus rode into Jerusalem on a young donkey (colt) that had never been ridden alongside another donkey. The disciples placed their cloaks on the colt for Jesus to ride. This is described as fulfilling the prophecy of Zechariah 9:9: "Rejoice greatly, O daughter of Zion! Shout aloud, O daughter of Jerusalem! Behold, your king is coming to you; righteous and having salvation is he, humble and mounted on a donkey, on a colt, the foal of a donkey."