How Old Was David When He Killed Goliath?

We know David wasn't expected to win against Goliath... but was the problem the fact he was too young, or something else? Let's look at how old David must have been when he fought Goliath.

How Old Was David When He Killed Goliath?

One of the most well-known stories in the Bible, second to the resurrection of Jesus, is the story of David and Goliath. It is this epic scene in 1 Samuel 17 of a young David standing against a nine-foot giant ( 1 Samuel 17:4) with only a sling and a stone to take down this mighty Philistine champion. But what do we know about David? How old was David when he killed Goliath?

Was David the Youngest Son of Jesse?

We are first introduced to David in 1 Samuel 16. God has rejected Saul as king and sends the prophet Samuel to Bethlehem in search of Jesse (1 Samuel 16:1). Jesse brings all his sons before Samuel, for the Lord said he would choose one of Jesse’s sons as the next king of Israel.

Seven of Jesse’s sons are brought before Samuel, but none are chosen. Samuel asks Jesse if he has any other sons, and Jesse replies, “There is still the youngest…but he is tending the sheep” (1 Samuel 16:11).

All in all, the Bible records that Jesse had eight sons and two daughters. In 1 Chronicles 2:13-17, we are told a little more about the family, but only seven sons are listed, with David being referred to as the seventh son. We are not told what the eighth son’s name is or where he falls in the birth order. David Tsumura’s commentary, The First Book of Samuel, makes this remark:

“… the Samuel passages, here and 17:12, probably adopt the practice of epic writing, explaining the number of Jesse’s sons as climactically ‘eight’ even though the actual number was seven, while the Chronicle passage follows the usual practice of listing the actual number, that is, seven, of sons by name.”

In 1 Samuel 16:11, Jesse calls David his youngest. There is some evidence that this phrase refers to David as the “runt” (MSG) or the least of Jesse’s sons. Even the Hebrew word used here, qatan, means not only young and small but also insignificant. Bible scholar Thomas L. Constable’s commentary on 1 Samuel 16 states this:

“The fact that Jesse did not have David present for Samuel’s visit, as his other sons were, may suggest that Jesse did not think as highly of David as he did of his other sons... Was David a neglected or even an abused child whom his father viewed more as hired help than as a son?”

Most commentators are torn on this subject. Pastor and therapist Ted Roberts suggest in some of his resources that an unhealthy relationship between Jesse and David could have been the root of David’s polygamist relationships later in life. Crosswalk editor G. Connor Salter summarizes Roberts’ idea as follows:

“David may have been stuck in a cycle of ‘sexual bondage.’ Like many men struggling with pornography or sexual issues, David had a harsh relationship with his father, who called David his “youngest son,” using a Hebrew word that also means “unimportant.

So, the fact David was the “last son,” may or may not mean “youngest son.” Can we learn anything about how old David was based on his service to Saul? 

How Old Would David Have to be as an Armor Bearer?

As we follow David’s story, we see him come to serve Saul and become one of his armor-bearers (1 Samuel 16:21). But did this happen before the battle with Goliath or after?

In Numbers 1:3, the Lord spoke to Moses and gave instructions for a census. As a part of the census, Aaron and Moses were to count all the men 20 years old and older to be a part of the army. So for David to be an armor-bearer for Saul, David had to be twenty years old.

Many commentators believe that the writer of 1 Samuel 16 and 17 does not go in chronological order, which makes nailing down David’s age at the time of Goliath and of being Saul’s armor-bearer a challenge. Dr. Thomas L. Constable’s Soniclight Notes say this: “A king appointed his armor-bearer to that position because of his courage, his ability to handle weapons, and his ability to get along with the king. David was probably a teenager at this time…”

This raises a follow-up question: can we get an idea of how old David was from Saul’s response to David asking to accept Goliath’s challenge?

Why Did Saul Think David Couldn’t Fight Goliath?

As we move through the story of David and Goliath, we come to the moment where David stands before Saul. King Saul looks at David and the confidence David displays in 1 Samuel 17:32, but then responds with, “You are not able to go out against this Philistine and fight him; you are only a boy, and he has been a fighting man from his youth.”

Again, given the ambiguity of the order of events in 1 Samuel 16 and 17, it is unclear whether Saul already knows David from his service as Saul’s harpist (1 Samuel 16:21). But the Hebrew word na’ar, translated as “youth” (v. 33), is a word to describe an older teenager.

In 1 Samuel 16:18, David is described as “…a brave man and a warrior. He speaks well and is a fine-looking man.” So, what was Saul’s hesitation?

Even Goliath thought David was small and weak when he said, “am I a dog that you come at me with sticks?” (1 Samuel 17:43)

Was he too small? Did Saul not want to lose the harpist that could calm his troubled mind? Or was Saul’s hesitation from fear of losing the battle, and thus a lack of faith? Saul had already lost favor with the Lord. Did he now fear the loss of the favor of his people and armies? We may never know for certain.

However, some later information gives us what we need to make a good guess about how old David was when he offered to kill Goliath.

How Old Was David When He Became King?

2 Samuel 5:4 states that David was 30 years old when he became king of Israel. If we do a little backward math, we can understand how old David was when he defeated Goliath.

Historians place the date when David was made king at the year 1010 B.C. If we add 30 years to that date, we estimate that David was born in 1040 B.C.

Before the death of Saul, David lived in Zilgag in Philistine territory for a year and four months (1 Samuel 27:7), which would make David 28 in the year 1011 BC. This is the only specific timing mentioned during David’s wanderings between 1 Samuel 21 and 1 Samuel 30. Writer and translator Lee Woofenden says, “Traditional Christian scholarship, then, has placed the period in which Saul sought David’s life and David fled from Saul at about seven years.”

But there is no consistency between scholars. The Jewish Tanakh suggests the chase between Saul and David was closer to eighteen months, while other scholars have estimated five to eight years. Bible.org contributor Robert L. Deffinbaugh states that “David had to wait for something like 15 years from the time he was first anointed by Samuel(1 Samuel 16)  to the time he became king over Judah (2 Samuel 2).” But again, this is an estimation.

In fact, we get the final piece of the puzzle from a brief reference in 1 Samuel, several years after David had killed Goliath. 1 Samuel 18:5 mentions that after David has served Saul well, Saul gave David a high rank in the army. He must have been at least 20 at the time he received the honor, due to the army requirements given in Numbers 1:3. This would mean that the events in 1 Samuel 17 take place when David is younger than 20. In 1 Samuel 17:42, Goliath looks at David in the Valley of Elah and calls him a boy. At the time of their battle, David does not look like a man worth fighting to the mighty Goliath. This lends credibility to the claim that David was a teenager at the time of his battle with Goliath.

Given this information, plus the data from all of Jesse’s sons, we can assume that David was between 13 and 15 when he fought Goliath. We don’t know where David’s sisters, Zeruiah and Abigail, fall in the sibling order, which would clinch how old David was. However, if we assume that Jesse’s wife had a child a year, with Eliab, Abinadab, and Shammah being of fighting age (over 20), that still puts David at the age of 15 (at the minimum 13) when he took his infamous stand against Goliath.

Photo Credit: Getty/pamela_d_mcadams 

Valerie Fentress Salem Web Network Contributing WriterValerie Fentress is the author of An Easter Bunny’s Tale and Beneath the Hood: a retelling woven with biblical truth. She aims to engage believers, especially kids, in the wonder and identity of who God is and who God made them to be. 

You can find out more about Valerie, her books, and her blog at www.valeriefentress.com.


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