They tie up heavy burdens

The scribes (Hebrew grammateis) are men who study the Torah and are looked upon to interpret it to the people.

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Many of them are members of the party of the Pharisees, a group of lay leaders whose authority lay in their ability to interpret the Torah, and in Jesus' day, were quite influential. Jesus acknowledges their social position and the unassailable ground of their authority: they “have taken their seat on the chair of Moses” (v 2). Yet, Jesus and these teachers differ in their interpretation of the Law. Their strict adherence to the letters of the Law makes the commands a heavy burden for the people. The detailed emphasis on following these laws is central to the teaching of the Pharisees, and not taking care to mitigate such things for people marginalized by their group adds to the burden. Jesus' own ministry, where the requirements of such things as Sabbath observance and purity codes are identified as impossible for poor peasants or the urban poor to follow, shows him as a gentle teacher. The observance of the commandments remains a “yo