We live in an age in which we often do not need to wait to know something.  Advancements in science allow parents to know the gender of a child months prior to birth and for genes to be mapped to determine possible future ailments.  Jesus tells the disciples something that is contrary to our time.  He tells them to wait.  They are to await guidance from the Spirit of truth.  When do you pray to the Spirit for guidance?  How hard is it to await the reply?  As we await the Spirit, we are putting our trust in God.