Christian apologist Alex McFarland defines “truth” as that which corresponds to reality, which is to say that our beliefs must be founded upon facts. Facts keep the real world running. Consider the constancy of gravity, electromagnetism, nuclear forces, mathematics, the periodic chart of the elements, the law of the harvest, the biological certainties of reproduction (i.e. DNA), and many other things.
Yet, far from standing upon the bedrock of facts, modern man seems to be carried away in the fluidity of a post-modern river of relative thinking. Ever trying (but never able) to get his feet underneath him to stand against the rapid currents of subjectivism, man struggles to keep from drowning in the torrential flow of opinion. Or, as the Apostle Paul worded it, “Ever learning, and never able to come to the knowledge of the truth“ (2 Timothy 3:7).
To simplify, the facts keep us in a world of physical normalcy. But the contrary thinking of our sin nature is to promote mankind’s own opinions, ideas, imaginations, dreams, speculations, whims, fancies, desires, and lusts (to name a few) above the constancy of the God Who is True (cf. Jeremiah 10:10).
All truth is indeed God’s truth because truth is founded upon the facts of God’s created universe. And the facts are that mankind is sinful. God is holy. Jesus, God’s Holy Son, died on the Cross. Jesus resurrected. God is willing and able to forgive all who will believe in Jesus. These are the spiritual facts. And these truths, any truth, and all truths will always and only correspond to the actual, not to the hopeful, regardless if the whole world holds to the contrary. Remember, truth is that which corresponds to reality.