Matthew Henry Commentary Judges 14:1-4

"And Samson went down to Timnah, and saw a woman in Timnah of the daughters of the Philistines. And he came up, and told his father and his mother, and said, I have seen a woman in Timnah of the daughters of the Philistines: now therefore get her for me to wife. Then his father and his mother said unto him, Is there never a woman among the daughters of thy brethren, or among all my people, that thou goest to take a wife of the uncircumcised Philistines? And Samson said unto his father, Get her for me; for she pleaseth me well. But his father and his mother knew not that it was of Jehovah; for he sought an occasion against the Philistines. Now at that time the Philistines had rule over Israel." — Judges 14:1-4 (ASV)

As far as Samson's marriage was a common case, it was weak and foolish of him to set his affections on a daughter of the Philistines. Should one, not only an Israelite, but a Nazarite, devoted to the Lord, seek to unite with a worshipper of Dagon? It does not appear that he had any reason to think her wise or virtuous, or in any way likely to be a helper suited to him; but he saw something in her pleasing to his fancy.

The one who, in the choice of a wife, is guided only by his eye and governed by his fancy, must then blame only himself if he finds a Philistine in his arms. Yet it was well done not to proceed until Samson had informed his parents about the matter. Children should not marry, nor take steps toward it, without the advice and consent of their parents.

Samson's parents did well to dissuade him from yoking himself unequally with unbelievers. It seems that it pleased God to leave Samson to follow his own inclinations, intending to bring good out of his conduct; and his parents consented, because he was set on it. However, his example is not recorded for us to imitate.