A sacrament is an outward sign instituted by Christ to give grace. In the 12th century, the tally of seven sacraments achieved acceptance. Sacraments are the primary means by which, through the grace of the Holy Spirit, we are united to Christ, restored or perfected in that oneness with Him, and help to draw others to Him. The sacraments have a visible and invisible reality, a reality open to all the human senses, but grasped in its God-given depths with the eyes of faith.
The visible reality we see in the sacraments is their outward expression, the form they take, and the way in which they are administered and received. The invisible reality we cannot "see" is God's grace, his gracious initiative to make us one with him by nuptial oneness with Jesus Christ, his son, in his death and resurrection.
God’s initiative here is a free and loving gift by which he offers people a share in his life, love and divine glory forever. This is what salvation is. Through these seven sacraments, God also works through us to extend this gift to others, indeed, to all the world.