In Reformed theology we talk about the ordinary means of grace. How would we define “means of grace?” Richard Muller answers this well:
media gratia: means of grace; i.e., Word and sacraments as the means by which the grace of God is operative in the church. The term is used by both Lutheran and Reformed orthodox, although the Lutherans often substitute a stronger term, organa gratiae et salutis, instruments of grace and salvation.
The identification of Word and sacraments as media gratiae does not intend to exclude a general or common operation of grace but rather it indicates the function of both Word and sacraments in the regeneration (regeneratio) and sanctification (sanctificatio) of man as the instruments or objective channels of special or saving grace (gratia specialis). Word and sacraments are thus instrumental both in the inception of salvation and in the continuance of the work of grace in the Christian life.
In addition, Word and sacraments are the sole officially ordained or instituted instruments or means of grace. God has promised the presence of his grace to faithful hearers of the Word and faithful participants in the sacraments. Thus the right preaching of the Word and right administration of the sacraments are the marks or identifying features of the true church (notae ecclesiae). Muller, Dictionary of Latin and Greek Theological Terms, sv media gratiae
Because God has promised to bless those who with true faith hear his word and partake of his sacraments, Reformed churches stress the importance of corporate worship. God speaks to us, blesses us, feeds us, helps us (etc.) through these means of grace, so we should want to be there every time he is graciously at work. Louis Berkhof said it well:
“God has appointed them as the ordinary means through which He works His grace in the hearts of sinners, and their wilful neglect can only result in spiritual loss.”
Therefore, let us not forsake assembling together (Heb. 10:25)!
Covenant Presbyterian Church (OPC)