1 Samuel 19:1

And Saul gave orders to his son Jonathan and to all his servants to put David to death. But Saul's son Jonathan had great delight in David.

1 Samuel 18:1

Now after David's talk with Saul was ended, the soul of Jonathan was joined with the soul of David, and David became as dear to him as his very life.

1 Samuel 18:9

And from that day Saul was looking with envy on David.

Treasury of Scripture Knowledge

Summary

And Saul spake to Jonathan his son, and to all his servants, that they should kill David.

Bible References

And saul

Ecclesiastes 9:3
This is evil in all things which are done under the sun: that there is one fate for all, and the hearts of the sons of men are full of evil; while they have life their hearts are foolish, and after that--to the dead.
Jeremiah 9:3
Their tongues are bent like a bow to send out false words: they have become strong in the land, but not for good faith: they go on from evil to evil, and they have no knowledge of me, says the Lord.
2 Timothy 3:13
Evil and false men will become worse and worse, using deceit and themselves overcome by deceit.

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain