Our apostle begins this chapter with wonder and admiration at the astonishing goodness and condescension of Alighty God towards believers, in taking them into his family, and adopting them into the number of his children; that strangers and enemies should be dignified with the honourable and amiable title of his sons; it is the same relation that Christ has, I ascend to my Father and your Father; there is indeed a diversity in the foundation of it; Christ is a Son by nature, we by favour; he by generation, we by adoption: However, not only crowns and sceptres are beneath his dignity, but the honour of our innocent state was not equal with it; well might the apostle then break out with an heavenly astonishment, and say Behold what manner of love is this, that we should be called, accounted and acknowledged, for the children of God!
Here note, 1. That it is the high and honourable privilege of all true believers, that they are now the sons of God.
They are Song of Solomon , 1. By regeneration; they are made partakers of the divine nature; not in the essence of it, but in the gracious qualities of it, which enables them in some measure to resemble God their Father; they receive a principle of spiritual life from God which enables them to live unto God: and this principle received in regeneration: it is an inward principle, an universal principle, a God exalting principle, and an abiding principle.
2. They are children by adoption also: adoption is the acceptance of a stranger into the relation and privileges of a son; it was a rare condescension in Pharoah's daughter to rescue Moses, an innocent and forsaken stranger, from perishing by the waters, and adopt him for her son; but O! how much greater kindness was it for Almighty God to save guilty and wretched man from eternal flames, and to take a rebel into his family! This privilege of being the sons of God by regeneration and adoption, is a choice and gracious privilege, an high and honourable privilege, a free and undeserved privilege, a lasting and abiding privilege.
Observe, 2. As the privilege itself, so the fontal cause of it, the fountain from whence it doth proceed and flow, namely, from the gratuitous love and free favour of God; what manner of love has the father bestowed upon us? He cannot say what, nor how great it was: He admires it, but cannot declare it; yet though adoption was the effect of God's free love, it was the fruit of Christ's rich purchase; he of a Son became a servant, that we of slaves might become sons.
Observe. 3. In the word, Behold! a note of attention and admiration both; God expects, the gospel requires, and the privilege of adoption deserves, that it be beheld with love and wonder, taken notice of with joy and thankfulness, and improved for growth in grace and advancement in holiness: Behold what manner of love the Father hath bestowed upon us?
Note here, That the believer's dignity though real and great, is altogether unknown to the unbelieving world; they are so far from acknowledging them to be God's children, that they mock and scoff, jeer and deride them, for pretending so to be; and as they little know them, so do they less affect and love them, but hate and persecute them. The world knoweth us not.
Note, 2. The reason assigned why the world knows not the children of God, Because it knew not him; God once made himself manifest to the world in and by his Son; Christ, in whom dwelt the fulness of the Godhead, came and dwelt among us, but the world knew him not, received him not; and if they saw no beauty in him, who had strength of grace, and no corruption in him, is it any wonder that they see no excellency in them in whom is much weakness of grace, and too great strength of corruption? Therefore the world knoweth us not, because it knew him not.