We don't often have trouble saying that God is good when good things happen to us; it's when bad things happen that we often struggle to say, "God is good."
We wonder how a good God could let such bad things happen. Can God really be "good" if He'd allow this... He could have stopped it... Why didn't He...
These are not uncommon questions to ask in bad situations.
Years ago, when I read the Book of Job for the first time, I was puzzled by Job's declaration, "Though He slay me, yet will I trust in Him." (Job 13:35)
I thought, "That's a rather odd thing to say about God. I've never known anyone to say that. Why would Job say, 'Though He slay me, yet will I trust in Him'?"
It didn't make sense to me. I thought we trusted in God because He brought good things into our lives. I had no idea that Job's response was actually the response of faith.
It was the response of Jesus in the Garden of Gethsemane, when He prayed that the cup of His suffering be taken from Him and the Father said, "No," and Jesus yielded Himself to the Father's will; even though it meant that the Father really would slay Him. [For it was the Father's will to crush Him - Isaiah 53:10]
It's the response of countless martyrs throughout the ages who went to their deaths praising God--convinced of His goodness.
It's the response of faith. We hold on to the conviction that God is good--because we know He is--no matter what happens to us; because the fact that God is good is unaffected by our circumstances; it is fact and like God, does not change.
Hold on to the goodness of God! And even though He slay you, trust in Him!