What does John 14:13 mean?
Jesus makes a promise in verses 13 and 14 which is routinely abused by well-meaning believers, ignorant critics, and cynical abusers. Key to understanding this statement is the context of Jesus' other comments about prayer and the will of God. It's also crucial to note the actual words stated, and not the mutations seen in pop culture. These remarks come in the middle of reassurances given to the disciples (John 14:1–11). They are especially tied to the comment Jesus made about His followers doing "greater" works that He did (John 14:12).The cornerstone of interpreting this verse is the qualifier Jesus provides: that requests must be made "in my name." This implies someone who is acting according to the will and authority of someone else. A cliché from old movies involves police officers shouting "Stop, in the name of the law!" The implication is they are speaking with the approval of a greater power. When a foreign ambassador says, "I agree to these terms in the name of the king," it means his ruler has given him the authority to make such a bargain.
On the other hand, people would probably laugh if a police officer said, "buy me coffee, in the name of the law!" Merely using that phrase does not guarantee the person to get whatever they want. They can only use that authority—and expect results—when they act according to the will of the law. And the law does not demand that random people purchase food for the officer. Anyone who says differently is either sadly mistaken, or an abusive fraud.
In exactly that sense, Jesus does not say, "I will give you anything you ask for." Nor does He say, "as long as you include the magic words 'in Jesus' name,' I will grant your request." Christ promises He will do anything that is asked "in my name." That implies that the person is asking something consistent with the will and nature of Christ. This, in turn, means such a request is consistent with the will and nature of God (John 14:10).
Likewise, Jesus notes the purpose for this promise, which is to glorify God. That also implies that requests which dishonor Him, or defy His will, are not expected to be granted. The following verse adds critical context to the situation: those who love God obey God (John 14:15). It stands to reason that those who love God will seek to ask according to His will, not in defiance of it.
Among the worst diseases infecting the church are those who preach God as a genie or wish-granting robot. Christ promises to meet our needs, and to grant requests that are legitimately "in His name." That does not mean we can redefine what we want as if it was something we need. Nor does it mean Christ vows to do as we tell Him, or as we see fit.