Is it possible for a minister to be a great blessing to people without him practicing what he preaches? Yes.

Scriptural examples:

Job 4:3-5:
3 Behold, thou hast instructed many, and thou hast strengthened the weak hands.
4 Thy words have upholden him that was falling, and thou hast strengthened the feeble knees.
5 But now it is come upon thee, and thou faintest; it toucheth thee, and thou art troubled.

Paul put it this way in 1 Corinthians 9:27:
But I keep under my body, and bring it into subjection: lest that by any means, when I have preached to others, I myself should be a castaway.

And Jesus said in Matthew 7:22:
22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?

This is why ministers must understand the nature of their assignment and that we will be judged by the life we lived and not only the messages we preached. The only way to ensure we are on the right track is to follow the order laid down by Jesus Himself

Luke said of Christ in Acts 1:1: The former treatise have I made, O Theophilus, of all that Jesus began both to do and teach.

Jesus did and then taught. Don’t just read a book and start to run with new information without first of all working out in you, at least in some measure, that knowledge. And if you are teaching from the knowledge you gleaned from others, be humble enough to know “I still have to practice this myself.”

If we follow this order, there will be less of a judgmental attitude in ministry and that false sense of superiority that comes straight out of the tree of knowledge and not the tree of life. Those who minister the fruits of the tree of life are merciful and faithful, compassionate folks.