"For the law was given by Moses, but grace and truth came by Jesus Christ." (John 1:17)
Without jumping into the (ongoing) theological debate over the boundaries of law and grace, I want to contrast, instead, the two concepts of grace and truth. It would seem these two fall within the limited scope of my ability to make some little comment on; perhaps, since I am a recipient of the former, and a continual seeker of the latter.
You have heard countless messages on grace, because, although the basis of our salvation is the substitutionary death and resurrection of Jesus Christ, the instrument that places it within our grasp is the grace of God. However, grace not only describes a situation when favor is shown where no expressed right is present; it also is used to describe a demeanor or means of presentation that is both favorable and pleasing.
Truth, for all its many would-be claimants, is personified in Jesus Christ (Jno. 14:6). This is not to say that truths cannot be obtained from others, but even these have their origin in Divine principle. Otherwise, they are only pseudo-truths. Truth, like its Source, is absolute and eternal. It cannot be sacrificed for anyone or anything.
But, having said this, I maintain that absolute truth and amiable grace are not mutually exclusive. In fact, they are complimentary. Truth will be more effective in your life, and in the lives of those you hope to influence, if it is accompanied by grace. Make no mistake; truth will remain truth, no matter how it is presented; but unless you show the grace that God showed you, any attempt to communicate it will be viewed with skepticism. (There is a difference between contending for the Faith and being just plain contentious!) On the other hand, you can show all the grace in the world to those you come in contact with, but if you compromise the truth in order to do it, you are a hypocrite of the worst sort, because you have clothed a falsehood with spiritual garb.
Not only did these two elements come by Jesus Christ, verse 14 says He was "full of grace and truth." So should we be. We should present the truth, uncompromisingly; and we should present it with all the grace we are capable of.
Grace without truth is inefficient; truth without grace is ineffective.