Q. I know there are blessings for ritual acts, but how about ethical duties like charity?
A. There is a distinction between commandments between man and God, such as hearing the shofar or wearing tefillin, and commandments between man and man like giving charity, acting justly, etc. The first group require blessings, the second do not.
One explanation is that we carry out these acts as God’s agents. We are doing God’s work; in a sense it is He who is carrying out these acts, not ourselves. The principle is, “As God is compassionate, so must you be compassionate”. Commandments between man and God, on the other hand, are being done by us for the sake of God.
According to another view, Torah commandments between man and God are unique to Jews and require a blessing.
Jews read Hallel, but not non-Jews; Jews kindle Shabbat lights, but not non-Jews. All cultures, however, have ethical standards, so being just, truthful, charitable, etc., are not unique to Jews. We do not say, “You commanded us” in relation to these duties, as all peoples are obligated to perform them, not just Jews.