How do we know who is telling the truth?

Faithless People, Faithful Prophet, The Backroom Boy is Honoured, I cannot tell how he will win the nations, The world passes away, Zion down but not out, The Painful and Perplexing Path from Famine to Feasting, God's Prescription for a Backslidden Church, A Revealing Reconciliation, God’s Great Provision in Great Adventures of Faith, Hope in Spite of Faithlessness.