Believers are under surveillance, and they are called to live so that neither their lifestyle nor their speech enable disbelief by others.
Because I know that you are obstinate,
and your neck is an iron sinew
and your forehead brass,
I declared them to you from of old,
before they came to pass I announced them to you,
lest you should say, “My idol did them,
my carved image and my metal image commanded them.” Isaiah 48:4-5
Walk in wisdom toward outsiders, making the best use of the time. Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person. Colossians 4:5-6
Paul concludes his letter to the church at Colossae with some final charges. They are to live wisely in their relationships with outsiders, that is, unbelievers. Two areas for concentration and care are the management of time and the quality of their speech. If a professing Christian is careless with his use of time, he enables unbelievers who observe him to discount either the genuineness of his profession or the veracity of his doctrine. More often than not, it is the latter option which prevails. By the same token, if the believer speaks in ways that are coarse, hurtful, lacking grace, or even corrupt (i.e. salt-less), he gives evidence that the gospel he professes is either not true or is powerless to change lives. Clearly, unbelievers are quick to grasp inconsistency in Christians to buttress their case against the call of the gospel.
God through Isaiah addressed another tendency of His disobedient, faithless people in Israel. The Lord tells them that His prophecies are designed to remove their claims that the deliverance which He planned for them was the work of their idols. It was a tendency in Isaiah’s day, and it continues to the present, for unbelievers to take credit for anything good that occurs, but to use problems and tragedies as an excuse to blame God or reject His existence.
Think about it
If you are identified with Christ, your life is under constant surveillance, not just by the Lord but, by your agnostic and pagan friends, relatives, co-workers, and neighbors. Be sure your life shows consistency with your profession. They may not believe because of you, but avoid making it easier for them to disbelieve.