Speaking of Saul, the Bible says the following 1 Samuel 10:6,10-11

Although opinions might differ on exactly what Saul’s turning into "another man" in 1 Samuel 10:6 means, one vital truth which is illustrated by Saul's anointing and life change is that God is able to transform his people and equip them with spiritual gifts for his service (1 Samuel 10:6; 1 Cor. 12:4-7). And it is only through this equipping and through the power of the Holy Spirit that we can be able to serve God's kingdom effectively.
Prior to his transformation, Saul, in spite of his great physical stature, lacked self-confidence and had no particular skills of leadership (1 Samuel 10:21-22). But after his anointing, we see God gifting Saul and equipping him for his ordained office.

We should be aware, however, that possessing spiritual abilities does not automatically correlate to godliness. A man may possess tremendous and famous spiritual gifts and still be condemned to Hell. Numerous passages in the Bible demonstrate that possessing spiritual talents is not synonymous with holiness. Exercising great spiritual gifts does not qualify someone to be a man of God.

The Example of the Generous Givers in Exodus 36

In Exodus 36, for example, Scripture tells us about the Jews who demonstrated the gift of giving. They generously gave gold and many other valuable items for the construction of the tabernacle. They gave more than enough and were continuing to give until Moses had to stop them because what they were giving was becoming too much.

In this incident, the gift of giving that led these people to generously give more than enough (Exod. 36:5) is very commendable as a model of cheerful giving. Unfortunately, however, Exodus 36:14-16, Exodus 32, and  Numbers 11, 14) indicated that the faith in the Lord and obedience to God's moral laws were sadly lacking in the lives of these people who were characterized by this great gift of giving!

The Example of the Ungodly Prophet in 1 Kings 13

To further illustrate the fact that spiritual gifts and godliness are not the same thing,  we see God using a lying old prophet in 1 Kings 13 as a means to convey His Word, in spite of his sins and deceit.

The Example of Balam in Numbers the book of Numbers

Furthermore, in Numbers 22-24, we see God using a prophet named Balaam who possessed a great knowledge of God and was equipped with significant spiritual gifts. In his day, Balaam had a reputation of being a genuine prophet who was equipped with significant spiritual gifts that's why Balak, the king of Moab was willing to hire his spiritual services. Balaam even received direct revelations from God. Yet this very Balaam, in spite of his eminent spiritual gifts, was not a man with a genuine heart after God as indicated in Numbers 22:7-8. Balaam's donkey was in fact more spiritually perceptive than the prophet because even though the donkey had no spiritual gifts, it at least obediently and submissively acknowledged his Creator. But the prophet who had wonderful spiritual gifts was also disobedient to God and he was not only referred to as a wicked man in several passages of scripture including Numbers 22:22-27, 2 Peter 2:15, Jude 11, and Revelation 2:14; but his end was also very tragic!

The Example of Judas Iscariot in the New Testament

In addition to this, even Judas Iscariot, who later betrayed Jesus, was also a great preacher with eminent spiritual gifts. He was actually among the 12 apostles who were sent out by Jesus on an evangelistic mission in Luke 9:1-6 with the spiritual gifts of casting out demons and healing the sick in Jesus' name. But in spite of possessing these spiritual gifts, Judas, with time, proved to be an apostate.

The Example of the Miracle Workers in the Book of Matthew

Scripture also tells us in Matthew 7:21-23 that on the day of judgment, there will be many eminent and prominent preachers who exercised great spiritual gifts in the world who will come to Jesus saying, "Lord, Lord, we have prophesied in your name—and in your name have cast out devils." And Jesus will say to them, "I never knew you!" And will send them to hell!

God's People who are Living in Sin Can also Exercise Great Spiritual Gifts!

From even among his own chosen people, God can choose to give spiritual gifts to redeemed people who are not spiritual but who are rather living in sin. Even in their backslidden state, God can choose to use these backsliders mightly for his glory. Of course, the fact that backslidden believers or pastors who are living in sin can sometimes exercise great spiritual gifts does not excuse their personal sin. God still holds them responsible for the sins in their lives and will bring them to account. This fact, however, serves again to demonstrate the fact that having spiritual gifts does not necessarily mean that someone who is exercising these great spiritual gifts is spiritual. Spiritual gifts and godliness are not the same thing. One can exercise great spiritual gifts without being godly. The case in point here is Samson whom we read about in Judges 13-16.

Although Samson appears among the list of the heroes of faith in Hebrews 11:32, none of the incidents that are recorded about Samson in the book of Judges were high-water marks of spirituality. I believe Samson was a man of faith who lived his life for God's glory for the greater part of his life which is not recorded in the Bible. The events that are recorded in Judges were just a tiny bit of his life which I believe lasted for a short period of time. But even in these low points, scripture tells us that the Spirit of God came mightily upon Samson and used him to achieve great things for the cause of God’s kingdom in the power of God’s Spirit — but without much godliness or faithfulness to God on the part of Samson.

In Judges 14:9, Samson who was himself a Nazarite from birth violated God's law (the Nazarite vow) that God had earlier on given to his people in Numbers 6:6-7. In Judges 14:2, Samson again disobeyed God by marrying a Philistine woman when he clearly knew that the law of God strictly forbade marriage to anyone outside the covenant community. When his parents warned him of the consequences of this action in Judges 14:3, Samson disregarded the warning and his parents left him. True, as indicated in Judges 14:14, Samson's parents did not know that "this was from the Lord" in the same way that the selling of Joseph into slavery in Egypt was of the Lord, but that did not make the human actions right. And by virtue of these facts, Samson in this period of time, was therefore not a clean vessel to be used. But God used him nonetheless and God manipulated circumstances in his favour and enabled Samson to curb the Philistines for God's glory.

Sometime back, I saw a quote on the Puritan Board which gives further clarification on this issue of God endowing mighty spiritual gift to an unclean vessel and here is what it said:

How then should we live?

The key lesson that we ought to learn from these examples is that God can give spiritual gifts to a man and in his divine providence, God may use that man's gifts to bring other people to Christ. However, that man himself, whose gifts God uses in healing the sick, casting out demons, and bringing others to Christ might end up dying and going to hell! There are many people who, like Judas, have already gone to hell and many are still going to hell even today loaded with spiritual gifts.

These truths should serve as a great warning to people who are manifesting prophetic or other supernatural gifts, but whose lives are at variance with the standards of Christ.

We should therefore not rest our confidence in either spiritual gifts or in external duties such as giving money to the church or attending public worship. Doing these things does not mean that someone is godly and they do not guarantee that person will go to heaven.

It is not spiritual gifts—but salvation by the grace of God through faith in Christ alone that makes a Christian! The greatest gift is the transformation of the new birth. For this reason, we should never put our confidence in gifts and abilities, but earnestly seek assurance that we are true children born of God (John 1:12-13). You might be having or desiring to have several spiritual gifts but are you truly a child of God? If you are not, then you need to be born again!

These facts also call for believers to be careful and not be mesmerized by miracle workers and rush to the conclusion that they are men of God. Scripture warns us in Matthew 24:24 saying that in the last days, Satans people who are described as "false messiahs and false prophets will appear and perform great signs and wonders to deceive, if possible, even the elect." Today we are living in the last days and we should be careful not to be deceived by those exercising great spiritual gifts.  We should test the spirits and see if they are of God. Jesus told us in Matthew 7:15-20 that you shall know them, not by their great spiritual gifts, but by their fruits.