Albert Barnes Commentary 1 Kings 2:36

"And the king sent and called for Shimei, and said unto him, Build thee a house in Jerusalem, and dwell there, and go not forth thence any whither." — 1 Kings 2:36 (ASV)

The object, apparently, was to keep Shimei under the immediate eye of the government. Shimei’s old home, Bahurim, lay east of Jerusalem on the road to Jericho (2 Samuel 17:18) and could only be reached by crossing the Kidron valley. Solomon assumes that if he quits the city, it will probably be in this direction (1 Kings 2:37).