Of course you have. We all have. Some of us have begged, implored, and pleaded with God to move in a particular manner and been left feeling like our prayers fell on deaf ears. In my experience, one of the primary reasons people struggle to believe in the goodness of God is unanswered prayer.
Furthermore, Jesus' own words in places like John 15:7 often add to our frustration. Jesus says, "If you abide in me, and my words abide in you, ask whatever you wish, and it will be done for you."
The problem is that when we weigh our personal experience against promises like this, many of us are left frustrated. We think, "I prayed, I asked Jesus to do something, and He didn't do it. Jesus said, 'Ask whatever you wish, and it will be done for you.' Well, it wasn't done for me. Jesus failed me!"
But here's the difficult truth: Inattention to the words of Jesus leads to the misapplication of His promises.
Jesus did not say, "Ask whatever, whenever, however you want, and I'll give it to you." Jesus is no vending machine. Your prayers aren't coins that obligate Him to spit out whatever you demand. Yes, Jesus promised to answer the prayers of His people. But He also prefaced this promise with the following conditions: "If you abide in me, and my words abide in you..."
To "abide" means to stay, to reside, or to remain. This implies more than mere memorization of Scripture. Jesus is not saying, "If you memorize a few verses, I'll answer your prayers." Jesus is saying that if you abide in Him and His words abide in you, then the full range of His life and teaching will dwell within you and inform your thoughts, feelings, and desires. The reason Jesus promises to answer these prayers affirmatively is that they're in line with His will.
The reality is that if God does not grant what we wish, it's because it's not in line with His good and perfect will. Abiding in Christ aligns us with His will. Our hope, our goal, our prayer should be to wish for God's will, to want what He wants, and to be desperate for what He desires. This is what it looks like to abide in Christ and for His word to abide in us. Where the words of Christ abide, the will of Christ will be wished for.
So the real question is, will you abide in Christ, and will His word abide in you?