Notice how casually Jesus slips in the word evil. He offers no argument for it; He simply assumes it. If you then, who are evil. The solidarity of the human race in sin is so basic to Jesus that He states it in passing while making a point about something else. This is the doctrine of original sin tucked inside a sentence about fatherhood. And notice who Jesus does not include: He says you who are evil, not we. The sinless Son of God stands apart from sinful humanity even as He speaks tenderly to it.
Then comes the move Jesus loves to make, an argument from the lesser to the greater. If even sinful parents give good gifts to their children, how much more will the Father in heaven give good things to those who ask Him. The question of this passage is not whether God is good enough to answer you. The question is, what kind of Father do you have?
For some, that word father lands hard. Your earthly father may have been absent, angry, cruel, or simply gone, and every mention of a heavenly Father passes through that broken filter. Hear this clearly: the good in our earthly dads is a faint pointer to the goodness of our heavenly Father, and the bad in our earthly dads is the photo negative of who He is. Whatever your dad was not, your heavenly Father is. Paul calls Him the Father of mercies in 2 Corinthians 1:3, the One who multiplies compassion to His needful, wayward, messy children. That is the Father who waits for you to ask.