What is a sacrament?

A sacrament is a holy ordinance instituted by Christ in his church,^[1] to signify, seal, and exhibit ^[2] unto those that are within the covenant of grace,^[3] the benefits of his mediation;^[4] to strengthen and increase their faith, and all other graces;^[5] to oblige them to obedience;^[6] to testify and cherish their love and communion one with another;^[7] and to distinguish them from those that are without.^[8]