Do people think you are out of your mind about the things of God?
For whether we be beside ourselves, it is to God: or whether we be sober, it is for your cause. For the love of Christ constraineth us; because we thus judge, that if one died for all, then were all dead: And that he died for all, that they which live should not henceforth live unto themselves, but unto him which died for them, and rose again. (2 Corinthians 5:13-15 KJV)
Paul is speaking to some around him who were expressing criticism of his teaching which was strictly based upon the commandments, teaching, and example set forth by God. Some had accused him of being out of his mind or not in touch with reality. Certainly they were basing their opinion on their own reality rather than forming it upon the truth of God.
Paul further explained that he was living unto the will of God in his life; whether it be considered by others that he was out of his mind or not. Whatever Paul was teaching, preaching, or mirroring in his life was all for the glory and honor of God according to the will of God for his life. People often find reason or cause to tear apart both the message and the messenger of God but Paul was committed to stand fast in this role God had called him to bring forth in this dark world.
Sowing seeds and spreading forth the message of the Gospel will always bring forth eager listeners as well as naysayers and critics, like Paul, never lose heart in doing the spiritual work God has for you.