1 Chronicles 10:13

So Saul died for his rebellion which he committed against the LORD, even against the word of the LORD, which he did not keep, and also for consulting a spiritist, to enquire of her

Leviticus 19:31

Do not return unto spiritists or seek after diviners, to be defiled by them. I AM your God.

Leviticus 20:6

And the person that turns after spiritists or after diviners to prostitute themselves after them, I will even set my face against that person and will cut him off from among his people.

1 Samuel 15:23

For rebellion is the sin of witchcraft, and to break the word of the Lord is iniquity and idolatry. Because thou hast rejected the word of the LORD, he has also rejected thee from being king.

Deuteronomy 18:10-14

There shall not be found among you any one that makes his son or his daughter to pass through the fire or that uses divination or an observer of times or an enchanter or a witch

Isaiah 8:19

And when they shall say unto you, Seek unto spiritists and unto wizards that peep and that mutter; shall the people not seek unto their God? Shall we appeal for the living unto the dead?

Exodus 22:18

Thou shalt not suffer a witch to live.

1 Samuel 13:13-14

Then Samuel said to Saul, Thou hast done foolishly; thou hast not kept the commandment of the LORD thy God, which he commanded thee, for now the LORD would have established thy kingdom over Israel for ever.

1 Samuel 15:2

Thus hath said the LORD of the hosts, I remember that which Amalek did to Israel, how he laid wait for him in the way when he came up from Egypt.

1 Samuel 28:7-20

Then Saul said unto his slaves, Seek me a woman that is a spiritist that I may go to her and enquire of her. And his slaves said to him, Behold, there is a woman that is a spiritist at Endor.

2 Kings 21:6

And he made his son pass through the fire and observed times and used enchantments and dealt with spiritists and diviners and multiplied much wickedness in the sight of the LORD, to provoke him to anger.

Acts 8:9-11

But there was a certain man called Simon, who before this in the same city used magic arts and amazed the people of Samaria, giving out that he himself was some great one,

Acts 16:16-18

And it came to pass, as we went to prayer, a certain damsel possessed with a Pythian spirit met us, which brought her masters much gain by divination:

Treasury of Scripture Knowledge

Summary

So Saul died for his transgression which he committed against the LORD, even against the word of the LORD, which he kept not, and also for asking counsel of one that had a familiar spirit, to inquire of it;

For asking

General references

Bible References

Even against

1 Samuel 13:13
Then Samuel said to Saul, Thou hast done foolishly; thou hast not kept the commandment of the LORD thy God, which he commanded thee, for now the LORD would have established thy kingdom over Israel for ever.
1 Samuel 15:2
Thus hath said the LORD of the hosts, I remember that which Amalek did to Israel, how he laid wait for him in the way when he came up from Egypt.

For asking

1 Samuel 28:7
Then Saul said unto his slaves, Seek me a woman that is a spiritist that I may go to her and enquire of her. And his slaves said to him, Behold, there is a woman that is a spiritist at Endor.

A familiar

Exodus 22:18
Thou shalt not suffer a witch to live.
Leviticus 19:31
Do not return unto spiritists or seek after diviners, to be defiled by them. I AM your God.
Leviticus 20:6
And the person that turns after spiritists or after diviners to prostitute themselves after them, I will even set my face against that person and will cut him off from among his people.
Deuteronomy 18:10
There shall not be found among you any one that makes his son or his daughter to pass through the fire or that uses divination or an observer of times or an enchanter or a witch
2 Kings 21:6
And he made his son pass through the fire and observed times and used enchantments and dealt with spiritists and diviners and multiplied much wickedness in the sight of the LORD, to provoke him to anger.
Isaiah 8:19
And when they shall say unto you, Seek unto spiritists and unto wizards that peep and that mutter; shall the people not seek unto their God? Shall we appeal for the living unto the dead?
Acts 8:9
But there was a certain man called Simon, who before this in the same city used magic arts and amazed the people of Samaria, giving out that he himself was some great one,
Acts 16:16
And it came to pass, as we went to prayer, a certain damsel possessed with a Pythian spirit met us, which brought her masters much gain by divination:

General references

Leviticus 19:31
Do not return unto spiritists or seek after diviners, to be defiled by them. I AM your God.