And this is his commandment - His commandment, by way of eminence; the leading, principal thing which he enjoins on us; the commandment which lies at the foundation of all true obedience.

That we should believe on the name of his Son Jesus Christ - See the notes at Mark 16:16. Compare John 16:1; Acts 16:31.

And love one another ... - This follows from the other, and hence they are mentioned as together constituting his commandment. Notes, John 13:35.

That we should believe on the name of his Son - We are commanded to believe on Christ, that for the sake of his passion and death we may be justified from all things from which we could not be justified by the law of Moses; and being through him redeemed from the guilt of sin, restored to the Divine favor, and made partakers of the Holy Ghost, we are enabled to love one another as he gave us commandment; for without a renewal of the heart, love to God and man is impossible, and this renewal comes by Christ Jesus.

And this is his commandment,.... Having mentioned the keeping of the commandments of God, the apostle proceeds to show what they are; that they are faith in Christ, and love to one another; which two are reduced to one, because they are inseparable; where the one is, the other is; faith works by love.

That we should believe on the name of his Son Jesus Christ; Christ is the object of faith, and he is no, as he is Jesus, a Saviour; faith deals with him as such, and will have no other Saviour but he: and now to believe in him, is not merely to believe that he is the Son of God, the true Messiah, the Saviour of the world, that he is come in the flesh, has suffered, and died, and rose again from the dead, is ascended into heaven, and is set down at the right hand of God, makes intercession for his people, and will come again to judge the quick and dead; but it is to go forth in special and spiritual acts upon him, such as looking at him, coming to him, venturing on him, trusting in him for life and salvation, committing all into his hands, and expecting all from him. And this is called a "commandment", and comes under the notion of one; not that it is properly a law, or belongs to the law; for faith in Christ Jesus is a fruit of electing grace, and a blessing of the covenant of grace; it is the free gift of God, and the operation of his Spirit, and is peculiar to the elect of God, and sheep of Christ; and so cannot belong to the law of works; but, as the Hebrew words, and both signify any doctrine, and instruction in general; see Psalm 19:7; so the word here used designs an evangelical doctrine, a divine instruction of our Lord Jesus Christ, in the Gospel, which declares that he that believes in Christ shall be saved; and so the word is used for a doctrine in this epistle, 1 John 2:7; and that of the next command or doctrine, which follows,

and love one another as he gave us commandment; that is, as Christ taught and instructed his disciples, John 13:34.

Believe on the name (πιστεύσωμεν τῷ ὀνόματι)

See on John 1:12; see on 1 John 1:7.

And this is his commandment, That we should believe on the name of his Son Jesus Christ, and love one another, as he gave us commandment.

3:23 And this is his commandment. The commandments may be summed up in one, with two parts, viz.: Faith in Jesus Christ, and love of the brethren.

3:23 And this is his commandment - All his commandments in one word. That we should believe and love - in the manner and degree which he hath taught. This is the greatest and most important command that ever issued from the throne of glory. If this be neglected, no other can be kept: if this be observed, all others are easy.

23. Summing up of God's commandments under the Gospel dispensation in one commandment.

this is his commandment-singular: for faith and love are not separate commandments, but are indissolubly united. We cannot truly love one another without faith in Christ, nor can we truly believe in Him without love.

believe-once for all; Greek aorist.

on the name of his Son-on all that is revealed in the Gospel concerning Him, and on Himself in respect to His person, offices, and atoning work.

as he-as Jesus gave us commandment.

3:22-24 When believers had confidence towards God, through the Spirit of adoption, and by faith in the great High Priest, they might ask what they would of their reconciled Father. They would receive it, if good for them. And as good-will to men was proclaimed from heaven, so good-will to men, particularly to the brethren, must be in the hearts of those who go to God and heaven. He who thus follows Christ, dwells in Him as his ark, refuge, and rest, and in the Father through him. This union between Christ and the souls of believers, is by the Spirit he has given them. A man may believe that God is gracious before he knows it; yet when faith has laid hold on the promises, it sets reason to work. This Spirit of God works a change; in all true Christians it changes from the power of Satan to the power of God. Consider, believer, how it changes thy heart. Dost not thou long for peace with God? Wouldst thou not forego all the world for it? No profit, pleasure, or preferment shall hinder thee from following Christ. This salvation is built upon Divine testimony, even the Spirit of God.