From Paul Miller and his book, A Praying Life —
Deep down, we just don't believe God is as generous as he keeps saying he is. That's why Jesus added the fine print — "ask in my name." Let me explain what that means...
Imagine that your prayer is a poorly dressed beggar reeking of alcohol and body odor, stumbling toward the palace of the great king. You have become your prayer. As you shuffle toward the barred gate, the guards stiffen. Your smell has preceded you. You stammer out a message for the great king: “I want to see the king.” Your words barely intelligible, but you whisper one final word, “Jesus. I come in the name of Jesus.” At the name of Jesus, as if by magic, the palace comes alive. The guards snap to attention, bowing low in front of you. Lights come on, and the door flies open. You are ushered into the palace and down a long hallway into the throne room of the great king, who comes running to you and wraps you in his arms.
The name of Jesus gives my prayers royal access. They get through. Jesus isn’t just the Savior of my soul. He’s also the Savior of my prayers. My prayers come before the throne of God as the prayers of Jesus. “Asking in Jesus’ name” isn’t another thing I have to get right so my prayers are perfect. It is one more gift of God because my prayers are so imperfect. Jesus’ seal not only guarantees that my package gets through, but it also transforms the package. Paul says in Romans 8:26,
Meanwhile, the moment we get tired in the waiting, God’s Spirit is right alongside helping us along. If we don’t know how or what to pray, it doesn’t matter. He does our praying in and for us, making prayer out of our wordless sighs, our aching groans. (quoted from The Message paraphrase of the Bible)