Spies planted in the crowd posed this riddle, hoping that Jesus would incriminate Himself.  The question was skilfully framed so that Jesus could be criticised whichever choice He made.  Supporting Caesar's authority and the punitive tax system would have inflamed the Jews against Him; but advising non-payment of taxes was a criminal offence for which the Roman authorities would have to put Jesus on trial.
 
However, there was not just one right answer: there were two.  Humanly they seemed mutually exclusive, but from God's perspective they were complementary.  Caesar was the governing authority established by God and therefore had a right to extract tax from his subjects (Romans 13:1-6).  On the other hand, God's people ultimately owed Him everything (1 Chronicles 29:14).  So, Jesus' reply was not only skilful in dodging the trap, but profoundly wise in teaching the truth: Caesar must have what belongs to him and God must have what belongs to Him.
 
Although it seems easier to exclude all but one possibility, and thus resolve all uncertainty, often more than one thing is true at the same time.  Indeed, most Bible doctrines have two apparently opposing 'faces'. For example, God is a God of love, but also He hates evil; God is One but has three persons; we are saved by God's grace alone, but also we must exercise faith to believe in what Christ has done for us on the cross; we live in a corrupted world, but this is not our home; one day we will die, but those who are in Christ will live forever; we are saved by God's grace through faith and no good works can contribute to our salvation, but faith without works is dead.  And there are many other examples.  Attempting to resolve each tension will produce a heresy - either by excluding one of the truths, or by merging them together in a way which removes the potency of each truth.
 
The believer is called to follow Christ holding truths in tension as we look towards Him – holding firmly to both.  In this world we have to hold equally true beliefs in tension because we are not wise enough to know how God will bring everything together.  If we could, we would live by rules and walk by sight: but we are called into a living dynamic relationship with God by faith.  It also means that we can never use our logic to outwit God; we are not called to control Him but to love and trust Him to bring everything together in Christ, even if we cannot resolve everything (Isaiah 55:8).