Kommentar zu Tehillim 119:148

watches Half the night, two watches, and according to one who says that the night consists of three watches, David would rise from bed at the first third of the night and engage in Torah until midnight, as it is said: “to speak of Your word.” From midnight on, he would engage in songs and praises, as it is said (verse 62): “At midnight, I rise to give thanks to You.”