Horatius Bonar: Not the quantity or quality of faith, but the object -- the person and work of Christ -- is our ground for righteousness before God

"The strength or kind of faith required is nowhere stated. The Holy Spirit has said nothing as to quantity or quality, on which so many dwell, and over which they stumble, remaining all their days in darkness and uncertainty. It is simply in believing -- feeble as our faith may be -- that we are invested with this righteousness. For faith is no work, nor merit, nor effort; but the cessation from all these, and the acceptance in place of them of what another has done -- done completely, and forever. The simplest, feeblest faith suffices; for it is not the excellence of our act of faith that does aught for us, but the excellence of Him who suffered for sin, the just for the unjust, that He might bring us to God. His perfection suffices to cover not only that which is imperfect in our characters and lives, but that which is imperfect in our faith, when we believe on His name." (Horatius Bonar, The Everlasting Righteousness, p. 58)

Horatius Bonar: Christ is Our Perfect Substitute

"To be entitled to use another's name when my own name is worthless, to be allowed to wear another's raiment because my own is torn and filthy, to appear before God in another's person––the person of the Beloved Son––this is the summit of all blessing. The sin-bearer and I have exchanged names, robes, and persons! I am now represented by him, my own personality having disappeared. He now appears in the presence of God for me (Hebrews 9:24). All that makes him precious and dear to the Father has been transferred to me. His excellency and glory are seen as if they were mine. I receive the love and the fellowship and the glory as if I had earned them all. So entirely one am I with the sin bearer that God treats me not merely as if I had not done the evil that I have done, but as if I had done all the good which I have not done, but which my substitute has done. In one sense I am still the poor sinner, once under wrath; in another I am altogether righteous and shall be so forever because of the perfect one in whose perfection I appear before God. Nor is this a false pretense or a hollow fiction which carries no results or blessings with it. It is an exchange which has been provided by the Judge and sanctioned by law; an exchange of which any sinner upon earth may avail himself and be blest." (Horatius Bonar, The Everlasting Righteousness, in "Not What My Hands Have Done," p. 42)

Horatius Bonar: Not Faith, but Christ, is our Righteousness

Horatius Bonar asserts that Christ, not faith, is our righteousness; faith simply unites us to Christ and is accounted unto righteousness (cf. Rom. 10:10):

Yet, after all, faith is not our righteousness. It is accounted to us in order to righteousness (Rom 4:5), but not as righteousness. For in that case it would be a work like any other doing of man and as such would be incompatible with the righteousness of the Son of God -- the “righteousness which is by faith.” Faith connects us with the righteousness and is therefore totally distinct from it. To confound the one with the other is to subvert the whole gospel of the grace of God. Our act of faith must ever be a separate thing from that which we believe.

… So faith is not our righteousness: it merely knits us to the righteous One and makes us partakers of His righteousness. By a natural figure of speech, faith is often magnified into something great; whereas it is really nothing but our consenting to be saved by another. Its supposed magnitude is derived from the greatness of the object which it grasps, the excellence of the righteousness which it accepts. Its preciousness is not its own, but the preciousness of Him to whom it links us. (Horatius Bonar, Not Faith, But Christ)