The Bible has been recognized as a Holy Book by Jews, Christians, and Muslims.  Its authors include lawgivers, historians, statesmen, laborers in orchards, shepherds, kings, poets, warriors, the victorious, the defeated, men of peace, prophets, owners of vast estates, and the impoverished. Here in this historical account, we are dealing with a clerical error.  

This should not make us in the least doubt the word of God, because the Bible also provides a correction.  The lesson for us is to harmonize the entire Bible and to earnestly study it when problems such as this occur.  The Lord will provide the solution.  From the Soncino press (a Jewish source) we quote: 

“The literal translation of 1 Samuel 13:1 is, ‘Saul was a year old when he began to reign, and two years he reigned over Israel.’ Both statements are palpably impossible, the first for obvious reasons, the second because, ‘It is difficult to believe that all the events of Saul’s reign could have been crowded into two years.’ The Rabbinic interpretations are either forced, or impose an impossible syntactical construction on the Hebrew words; e.g. ‘Saul was as sinless as a year-old babe’ (Midrash); ‘in the first year of Saul’s reign’ (Rashi); ‘Saul had been king one year when his rule was confirmed in Gilgal’ (Kimchi, Ralbag); ‘when he had reigned for two more years he set up his standing army’ (Ralbag); ‘he reigned for two years before David was anointed king’ (Rabbi Isaiah). We are forced to the conclusion that the complete numerals are wanting in the Hebrew text, not only in the first clause, but in the second as well and any attempt to supply the numbers can only be conjectural.’ “

We agree with this conclusion.  An obvious clerical error of transmission occurred sometime between 1,000 B.C. and the 2nd century B.C. since the Greek translation of the Old Testament has the same reading.   

We need not worry.  We need not question the Bible’s authenticity.  However, the Lord in safeguarding the Bible more than fully provided a correction for this mistake.  The Apostle Paul, addressing a Jewish synagogue told them what everyone already knew – Saul’s reign was forty years.  Paul says in Acts 13:21, “And afterward they desired a king: and God gave unto them Saul the son of Cis, a man of the tribe of Benjamin, by the space of forty years.

We know that Paul was supplying what the scholars had reconstructed from the records, since Josephus, the Jewish historian writing in the first century, gave the same length of Saul’s reign (Antiquities 10.8.4), writing, “Now Saul reigned eighteen years while Samuel was alive and after his death [twenty] two years.” 

God is more than able to fix clerical errors and he has done so here.

Additional Resources:

Christian Questions Podcast 5-part series “Has the Bible Been Mistranslated and Misunderstood?”
Discovering and authenticating how the Bible came to be

Christian Questions Podcast Episode #875: So, Where Does the Bible Come From?
The “how” and “why” of the books of the Bible
CQ Rewind Show Notes