Therefore, if you are presenting your gift on the altar and there you remember that your brother has something against you,
Here Jesus emphasizes that the offering or worship presented to God must be carried out with a pure heart and in the context of peaceful relationships. When someone comes to the table to present his offering to God (which may be a sacrifice or an act of worship), but remembers that his brother (or any other person) has a complaint or hurt against him, this means that those relationships must be put in order as a first priority, which we will see next in Matthew 5:24.