'Observe' in the Bible

"The rest of the people, the priests, the Levites, the gatekeepers, the singers, the temple servants, and all who separated themselves from the peoples of the lands to [observe] the law of God--their wives, their sons, their daughters, and all who know and understand--

[are] helping their brothers, their nobles, and entering into a solemn oath to walk in the law of God which was given by the hand of Moses the servant of God, and to observe and do all of the commandments of Yahweh our Lord and his judgments and regulations.