This is one of my favorite videos on YouTube. It is a video of SalvationbyGrace.org by Pastor Jim McClarty. Understanding the indicative and the imperative truly opens up scripture. If you get this concept then you will understand; "If you love Me, you will keep My commandments." (Jn 14:15 NASB).
Salvation from the wrath of God that we all deserve for our sin is a gift, by His grace alone, through faith alone, in Jesus Christ alone.