Truth is the first moral imperative. In fact, you could almost go so far as to say it is the ONLY real imperative--or at least the one upon which all else rests. Now, my fellow Christians would say, "Well, but doesn't 'love' get the most attention in Scripture?" They do have a point, but let me explain why I think it is a simplistic point. Jesus is quoted, thusly, in the Gospels;
"Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, Thou shalt love thy neighbor as thyself. On these two commandments hang all the law and the prophets." Matthew 22-37-40...
...that is a COMMANDMENT. It is not the greatest principle upon which the universe, and both the physical and spiritual realms operate. He was not ASKED the question some would think He answered there. Truth is beyond that question... It is the principle upon which relationships operate, and that is what was important to the questioners and to Jesus at that time and place. Truth is the basis for all love. That, my friends, IS TRUTH. In other words, without truth you would not, and could not, even have relationships, living organisms, or; of course...people...or a God to love, and from whom to hope for love in return. Truth is the "universal causative" I like to call it...or you might prefer: "Truth is the very mind of God." Simply put, truth is the basis to all human relationships, and God/human relationships.
Without truth none of the laws of nature would work. The heavenly bodies would spin out of control. Gravity, time and motion, the operation of light and all infinitely small particles that hold everything in the physical world together, would simply cease. In other words, we would have complete and utter chaos...sort of like the Bible describes the world before the creation..or; as the secular scientist describes the universe before the "big bang." Simply put, truth is the basis to all the physical laws of the universe.
If truth went away, suddenly, and in an instant everything would cease to be.
Truth is what gives rise to law...all law...physical, temporal, human, spiritual, etc. Truth infuses these concepts and gives them life. This is why evil hates truth so desperately. This is why the current "powers-that-be" have even gone so far as to grant themselves "the right" under color of law to LIE to the people they are supposed to serve and represent. This is why, as the Bible says "there is no truth in them." You see, without truth IN YOU, you are already dead. You are a zombie. You are separated from God and simply awaiting the final punishment.
Truth is the lifeblood of the universe. You can not truly love somebody before you first commit to honoring what they are..everything you like about them...i.e. "their truth." Simply put, again, truth is the basis for all love, and for all laws that protect humanity's ability to love properly, fully, righteously and IN TRUTH.
You might have others sight Hebrews which elevates the importance of faith:
"Now faith is the substance of things hoped for, the evidence of things not seen." --Hebrews 11:1
...but surely without truth there is nothing in which to place your faith. Faith is believing without seeing...in other words it is trusting in the source of something greater..something omniscient..something good that is telling us what is right and good (and true.) But truth is what gives life to faith. If we were to put our faith in something untrue....say a government telling us about the origins of a great terror attack...then everything we put our faith in is a lie, and the lie grows and grows and becomes 'ANTI-TRUTH' ...'ANTI-FAITH'...'ANTI-LOVE'...and yes, even AntiChrist.
Truth is the prerequisite to all things...to life, to the universe, to order, to a civil society...to love, and faith.
TRUTH = GOD (however you choose to define HIM.) Without truth we have nothing.