In 1 Corinthians 6:12, Apostle Paul speaks about three different levels at which people can live.
"All things are lawful, but not all things are profitable". The unlawful (or unrighteous) level is where most unbelievers live. No believer should ever descend to this level - but unfortunately some do. If they persist in living there, they will lose their salvation. The minimum level for a believer is the next level - lawful (or righteous). But there is a still higher level - the profitable. Out of 100 things, 70 things may be unlawful. So we should not do any of them. But we can do any of the remaining 30 things that are lawful. But out of those 30 things, only 10 may be truly profitable spiritually. A wholehearted Christian will do only those 10 things.
But a halfhearted Christian will choose from any of the 30 lawful things. If you want to be a wholehearted, effective servant of God, then you will have to select the profitable things from the lawful things.
Consider the example of time. We all have 24 hours a day. If you spend part of that time watching dirty movies or reading dirty books, that would be an unlawful way of spending your time. On the other hand, there are many lawful ways in which you can spend your day. Some of those things are necessary and we have to do them. But you could spend many hours reading the newspaper - which though lawful may not be the most profitable way to spend the day.
If you want to be a useful servant of God, you will need to be disciplined and cut out some of those unnecessary items from your daily routine and spend more time in the things of God. You can choose to spend many hours surfing the Internet (on clean sites) or even watching many Christian TV programs and then have very little time left to study the Bible. Or alternatively, you could spend a short while surfing the Internet (for world news, etc.) and have much more time to study the Bible. You are not sinning if you spend two hours watching a clean TV program or visiting a clean Internet site; but it may be a waste of time that could have been spent more profitably studying God's Word or helping needy people.
In the same way there are unlawful ways of spending money, lawful ways and profitable ways. A wholehearted Christian will use his time and his money only in profitable ways. We must learn to make the right choices.
The secret of a godly life lies in the choices we make. Out of all the lawful things we can do with our time, we must choose the best way to spend it. Out of all the lawful ways in which we can spend our money, we must select the best ways. Such a man will count for God.