“Ye observe days, and months, and times, and years.”
King James Version (KJV)
4:10 Ye observe days - Jewish sabbaths. And months - New moons. And times - As that of the passover, pentecost, and the feast of tabernacles. And years - Annual solemnities. it does not mean sabbatic years. These were not to be observed out of the land of Canaan.
Ga 4:10 Ye observe. These are specifications of how they were "turning back" to the Jewish law. Compare Col 2:16. Days. The Jewish Sabbaths. Months. The new moons. Times. The Jewish festivals. Years. The Sabbatical years. In observing these there was legal bondage to an obsolete system.