Mephibosheth was the name of two men of the family of Saul, who is stated in the books of Samuel of the Hebrew Bible to have been the first king of ancient Israel:
Some years later, when King David had subdued all the adversaries of Israel, he recalled the family of Jonathan, and discovered that Mephibosheth was residing in the house of Machir. So he sent royal messengers there, and brought Mephibosheth and his infant son Micah to Jerusalem, where they resided from that point on (2 Sam. 9).
When David was a fugitive, according to the story of Ziba (2 Sam. 16:1-4), Mephibosheth proved unfaithful to him, and Ziba was subsequently awarded all of Mephibosheth's estate. However (2 Sam. 19:24-30), Mephibosheth later told David that he had remained loyal to him, and that Ziba had lied. David then ordered the estate divided between the two. Mephibosheth allowed Ziba to keep everything as he was simply content in knowing that David was safe. After this incident, Mephibosheth is only mentioned as having been protected by David (2 Sam. 21:7).
This article incorporates text from Easton's Bible Dictionary (1897), a publication now in the public domain.