What happens in your heart when I say "Heavenly Father"? What picture comes to mind? Some of us, through life experiences, have a broken concept of "father". Maybe your idea of a father is someone cold, or someone cruel, or just someone not there. But the Bible tells us that our Heavenly Father quiets us with His love, and rejoices over us with singing. God holds us in His arms like a father holds his newborn in the hospital, with tears of joy streaming down his face.
I once read a story about a young man who grew up in a terrible, abusive situation. But every day Mr. Rogers would come on TV, and this young man would tell himself, "My dad might be a bad dad, but look at this man! This is what a good dad can be like!" He was able to make it out of his childhood with a positive attitude and hope for the future, because he didn't allow his idea of "dad" to be written by one bad man.
Maybe you've become stuck believing all fathers have the same flaws as your earthly father. But take a moment to observe the other fathers around you. Get to church early and watch the dads as they come in. Watch them as they hug and kiss their children. Watch their eyes light up when they pick up their kids from Sunday school. See how they respond without raising their voices or their hands in anger. Begin to notice how fathers can be good, and then remind yourself, "That's how my perfect Heavenly Father loves me!" (You'll never find a perfect father here on Earth, but they can help you find your way.)
We all make mistakes when it comes to representing the love of God to our children, our spouses, our friends, and our neighbors. Whether your father was trying his best or couldn't care less, you need to forgive him (Matthew 6:12). The best way to do that is to spend time remembering our own flaws and our need for a savior. Romans 5:8 teaches us that "...God demonstrates His own love toward us, in that while we were still sinners, Christ died for us." If God can do that for us, his enemies, we need to try to do that for our fathers.