How did Israel keep the Law while lacking faith?
Israel observed the Feast Days, offered the prescribed sacrifices, and followed the Law to the letter outwardly. Yet they did so without faith, attempting to establish their own righteousness by works rather than submitting to God's righteousness. Scripture says without faith it is impossible to please God, so their law-keeping could not satisfy Him.
Les explains that Israel kept the Feast Days and would not miss one, followed the sacrifices, and observed the Law to the letter, but with no faith. They were ignorant of God's righteousness, going about to establish their own righteousness and not submitting to God's righteousness. They tried to do it with their own works, leaving faith out, just as many today follow rote and ritual without faith, which counts for nothing. Christ was the object of faith Israel was expected to embrace; He fulfilled over 360 Old Testament prophecies, yet they did not recognize Him because they did not know their Bible. Without faith it is impossible to please God, true in the Old Testament economy as today.