Whatever you do, do it heartily, as to the Lord and not to men.
Colossians 3:23 (NKJV)
Why do many Christians feel producing high-quality work at work is necessary, but that it is irrelevant when it comes to church ministry? Is it because they are afraid of receiving a poor appraisal or losing their job for poor office performance, whereas in church it is all voluntary, and so no one can insist on excellence from them?
Why do the same believers become upset and threaten to leave when their church leaders gently remind them of anything they have not done right or properly? If the same thing happened at work, they would quickly admit their shortcomings and resolve to do better.
Perhaps the issue is spiritual rather than behavioural; that is, poor attitude and tardiness at church are more "acceptable" since "we are under grace, not law." The truth is that there is no reason for you to take your church work less seriously than your workplace work, whether paid or volunteering.
The Apostle Paul tells us that we do not operate on two different work ethics, but that we always give of our best since we are doing everything for the Lord. The Greek word for "heartily" is psyche which means "the breath of God's life". It is the root word from which we derive the word psychology in English. In other words, our Christian "psychology" of work (attitude, ethics, and values) should mirror God's abundant life in us. This is a representation of the gospel rest.
Catch "the breath of God" in everything you do. Seek to live consistently from this revelation. It will change the way you live and serve God and others.