Babbie Mason with Eddie Carswell wrote “Trust His Heart”. In an interview, Mason said the song was influenced by a North Atlanta pastor who “became inspired by the words that Charles Haddon Spurgeon had coined in his writings, ‘God is too wise to be mistaken. God is too good to be unkind. And, when you can’t trace His hand, you can always trust His heart.’”
Similar quotes are found in The One Year Daily Insights with Zig Ziglar and The Lucado Life Lessons Study Bible.
Spurgeon’s actual wording is found in his sermon “A Happy Christian”:
The worldling blesses God while he gives him plenty, but the Christian blesses him when he smites him: he believes him to be too wise to err and too good to be unkind; he trusts him where he cannot trace him, looks up to him in the darkest hour, and believes that all is well.source