Jg 7:2 And the LORD said to Gideon, "The people who are with you are too many for Me to give the Midianites into their hands, lest Israel claim glory for itself against Me, saying, 'My own hand has saved me.'
Although what the Lord is talking about here is physical deliverance, the intent and design of His rescues and redeeming acts are the same---no creature should deprive Him of the glory that rightfully belongs to Him.
And it is just exactly so with spiritual salvation. Ephesians 2:8-9 says:
Eph 2:8 For by grace you have been saved through faith, and that not of yourselves; it is the gift of God,
9 not of works, lest anyone should boast.
If you can contribute something meritorious to effect your salvation, then you have robbed God of the full glory that rightfully belongs to Him alone.
The scheme of salvation must be in a way that our mouths can only glorify
God 100% of the salvation that was wrought on our behalf. The only way for that to take place is salvation by grace through faith in the Savior and what He did on the cross. A salvation that is not the result of our own efforts. A salvation that we could never proudly claim: "My own hand has saved me."
