In John 1:14 you learn about the relationship between Jesus and God - Jesus Christ as his one and only Son. Jesus came down to glorify his Father in the flesh, meaning he is still fully divine and came fully human. He also came full of grace and he came full of truth. That was his message to us.
Jesus, the Son Of God, became man and dwelt among his people for a purpose. He came as grace and truth. These two words together are quite interesting if you think about it. God coming down as a man was showing a different way to govern. Yes he came to share what is right, true and holy but he also came with an unmerited favor of God. Quite simple an undeserved favor.
Jesus was our living example, our perfect example. How he lived and communed with God, how he walked and shared his life with others should be our goal as Christians. His message of grace and truth should be our message. I pray as you wear this shirt, you exemplify what it means to follow Jesus. To live a life full of grace and truth.