C. F. Keil and Franz Delitzsch on Isaiah 43:25

Isa 43:25

Nevertheless, the sustaining power of divine love is greater than the gravitating force of divine wrath. “I, I alone, blot out thy transgressions for my own sake, and do not remember thy sins.” Jehovah Himself here announces the sola gratia and sola fides. We have adopted the rendering “I alone,” because the threefold repetition of the subject, “I, I, He is blotting out thy transgressions,” is intended to affirm that this blotting out of sin is so far from being in any way merited by Israel, that it is a sovereign act of His absolute freedom; and the expression “for my own sake,” that it has its foundation only in God, namely, in His absolute free grace, that movement of His love by which wrath is subdued. For the debt stands written in God’s own book. Justice has entered it, and love alone blots it out (mâchâh, ἐξαλείφει, as in Isa 44:22; Psa 51:3, Psa 51:11; Psa 109:14); but, as we know from the actual fulfilment, not without paying with blood, and giving the quittance with blood.