1 Samuel 18:26
And when his servants told David these words, it pleased David well to be the king’s son in law: and the days were not expired. And when his servants told David these words, it pleased David well to be the king’s son in law: and the days were not expired.
The verse belongs to the larger history from 1 Samuel 7 to 18 that tells of the choosing of Saul as king, the death of Samuel, and the waning of the house of Saul with the calling of David. Its immediate setting is after the victory over Goliath, when Saul gave his daughter Michal to David as wife and made David captain of a thousand. It belongs to the account of David's rise as champion of God's people, Saul's fierce jealousy, and the beginning of the friendship between David and Jonathan. It belongs also to the account of Saul's jealousy and effort to slay David, the covenant between David and Jonathan with Jonathan's noble and unselfish generosity, and the contrast between jealous Saul and his noble son.
David's honors and advancement made Saul wretched with envy, and David's growing popularity increased Saul's jealousy and hatred. David's distinguished victory and service led Saul to suspect that David was the man God had chosen to take his place as king. The verse shows David was pleased with the prospect of becoming the king's son-in-law and willingly undertook the task set before him. The marriage was not to take place on the day the promise was made, for David first had to fulfill the condition of killing one hundred Philistines, and the statement that the days were not expired set a future period for that work.
The word this day in Saul's promise referred to when he made the promise, not to when it would be fulfilled. In the related account David struck down the one hundred Philistines and God delivered them to him. The story presents David as showing a noble spirit in contrast to Saul's rashness, avoiding Saul without retaliating against the ruler of his people. It presents David's unfailing loyalty to Saul, against whom he never lifted his hand though Saul sought to slay him, and his hope and trust in God with utter refusal to take vengeance into his own hands against the enemy pursuing him.
It is part of an interesting narrative with important lessons that gives light and new suggestions to the real Bible student, teaching that it is safe to commit one's cause into the hands of God. David's zeal in pursuing that undertaking is held up as an example for setting and pursuing a goal.