Sovereign grace is not a religious denomination or theological movement. It is a concise expression of the clear teaching of scripture that describes who God is and how He saves a sinner.
God is sovereign. He is the most high God (Gen 14:22), supreme and elevated in authority, character, dignity and worth above all His creatures. He is not accountable to anyone (Job 33:13). He does as He pleases, when He pleases, with whom He pleases (Is 46:10). He is not dictated to nor influenced in any degree by anyone or anything and cannot be questioned or hindered in anything that He does (Dan 4:35, Rom 11:34).

Grace is God’s eternal favor and blessing upon a sinner who neither deserves it nor seeks it. Grace is salvation. Grace is Christ and all of the benefits of His meritorious life and sin-atoning death bestowed upon the wretch who is worthy of only condemnation and punishment.

Sovereign grace is the sovereign God purposing and promising to be gracious to whom He would be gracious, and then bringing to pass that purpose and making good on that promise by putting those objects of grace in Christ and Christ in them (1Cor 1:30, Col 1:27). - Chris Cunningham