Encouragement to keep knocking, to keep asking. I've fallen into an overthinking pattern lately that's left me needing to hear this particular passage; I somehow reasoned myself to a place of thinking that it was "more right" to just pray for God's will to be done in whatever given situation instead of making specific intentions. That praying "May Your will be done in X's life" was what I ought to be saying, rather than "Please help X to get better." And because of this, praying for people was starting to be a source of stress and confusion and even guilt.
But right here we have Christ instructing us to bring those specific petitions to God: "Ask, and it shall be given you: seek, and you shall find: knock, and it shall be opened to you." God does want me to bring my needs and particular prayers to Him, and even to continue doing so over and over again.
Understanding that prayers may not be answered the way I think they should be is still important, of course; God sees everything, and I see only a small part, so any time one of us is wrong about what the best course of action is, it's always going to be me. But even in spite of my shortsightedness, God invites me to ask, to seek, to knock. What a gift!