Believers should have confident assurance of their salvation, but on what grounds? I’ve explored several options and have commended a richly trinitarian understanding of salvation as the ultimate basis of assurance. Confidence in God and his salvation rests in intelligent belief in the Trinity.
The reason for this is that, to put it as concisely as possible, the Trinity is the gospel. Trinity and gospel are not just connected in some distant way, as two ideas which can be related to each other by a long train of reasoning. The connection is much more immediate than that. Seeing how closely these two go together depends on seeing both Trinity and gospel as clearly as possible, in a large enough perspective to discern their overall forms. When the outlines of both are clear, we should experience the shock of recognition: Trinity and gospel have the same shape! This is because the good news of salvation is ultimately that God opens his own trinitarian life to us. Every other blessing is either a preparation for that or a result of it, but the thing itself is God graciously taking us into the fellowship of Father, Son, and Holy Spirit, to be our salvation.
Here for certain we have a truth which evangelicalism has always grasped firmly. It is the central idea of that beloved text John 3:16, that we can see the extent of the Father’s love for the world by attending to the greatness of the gift which he gave for our salvation: his Son. And it is at this point, where God’s self-giving is most conspicuous, that we are forced to break through to explicitly trinitarian confession if we want to go any further. For in the case of God, “himself” is not a word that points to an isolated individual existing alone with his aloneness. When God finally fulfills all his promises by giving himself to be our salvation and our shield, this takes place as the Father gives the Son.
The index of how much God loves us is how much he gave to accomplish our salvation. Paul drives this point home as the climax of his far-ranging argument in Romans 8, grounding Christian hope and assurance in the fact that since God has already given his own Son, it obviously follows that nothing is too great for God to give. Dwight L. Moody, sometimes called “Mr. Evangelical,” preached frequently on this theme, and one of his last sermons was on the text of Romans 8:
Now Paul puts some questions. ‘Who can be against us? He that spared not His own Son, but delivered Him up for us all, how shall He not with Him also give us freely all things?’ (verse 32). When God the Father gave Christ, the Son of His bosom, He literally gave up all that heaven had. He gave the richest jewel that heaven possessed. And if He has given us His Son, is there anything too great for us to ask? If a man should give me a diamond worth one hundred thousand dollars, I think I would make bold to ask him for a little piece of brown paper to carry it away in. If the Lord has given me the Son of His bosom, I can ask for anything. How shall He not freely give us all things?
When we consider the gospel of salvation in Christ, we are not dealing with the outer fringes of God’s ways, but with the very core and center of who God is. God is not trifling with us in the gospel, but opening up in the most intimate way his very heart. Of course God remains incomprehensible, mysterious, and far above all created things in a way that is not at all diminished by the way he makes himself lavishly available to fallen humanity in the economy of salvation. But his infinite transcendence over all created things cannot be construed as any kind of reserve or standoffishness. The Father’s giving of the Son renders that interpretation impossible. Having sent servants already, God takes the ultimate step and reaches out to his people by sending an agent more dear and intimate to himself: “What shall I do? I will send my beloved son; perhaps they will respect him.”
The Puritan Thomas Goodwin brought all of these insights together tersely when he said that “the things of the gospel are depths —the things of the gospel…are the deep things of God.” Goodwin loved to ponder the many ways in which the gospel was a mystery. He noted that this gospel was the thing into which prophets “inquired and searched diligently,” and that angels “longed to look into” its content. But beyond this, Goodwin said, it was a mystery in the sense that God himself considered it uniquely precious, because it “lay (as I may so speak) at the bottom of his heart, the great secrets, which he esteemed such even from everlasting.” Goodwin is drawing language not from Ephesians but from First Corinthians when he speaks of “the deep things of God.” In the second chapter of this letter, Paul puts great emphasis on how profound, secret, and inaccessible to human understanding the blessings of the gospel are. What has been made known to us in the gospel is “what God has prepared for those who love him,” and far from being conformable to human wisdom, it is something which
no eye has seen,
nor ear heard,
nor the heart of man imagined,
words which most Christians probably associate with heaven, but which Paul clearly intends with reference to the present revelation of the gospel. If this divine wisdom has now been handed over to us in the gospel, it is by miracle, because these are things whose origins lie so deep within the heart of God that only God can know them. The mystery of the gospel is locked up inside of God, and can only be communicated by someone who is God. Paul underlines this three different ways:
We speak God’s wisdom, which God predestined before the ages to our glory
To us God has revealed them through the Spirit, for the Spirit searches all things, even the deep things of God. Who knows the mind of a man except the spirit of the man, which is in him? Even so the thoughts of God no one knows except the Spirit of God.
Who has known the mind of the Lord, that he should instruct him? But we have the mind of Christ.
The predestining Father determined this mystery; and the depth-searching Spirit has access to these depths because he is as intimate with God as my spirit is with me. But that same Spirit has revealed them to us, and we therefore have come into harmony with the mind of Christ, the one who knows the mind of the Lord. Note that the Spirit and Christ have brought out into the open a mystery which has its natural home at the center of God’s heart, at the depth of his life. This opened secret is the gospel. It has such a profound and divine character that even to make it known, God must give himself over for its revelation. That revelatory self-giving is perfectly in line with the content of the thing revealed, which is that God gives himself to us to be our salvation. He does not dispense blessings, but himself.
Trinitarian soteriology, then, grounds the assurance of salvation. I give the last word to nineteenth century American theologian Benjamin Morgan Palmer, whose excellent little book The Threefold Fellowship and the Threefold Assurance draws these connections in a powerful way.
The relation of the Father, the Son and the Holy Spirit to man corresponds to a relationship in God between the Father, the Son and the Holy Spirit; and the love which is poured out to save us is the expression of that love which has dwelt eternally in the bosom of God. The gospel scheme of salvation not only has its origin in the infinite grace and mercy of God, but also finds its method and its execution in his threefold personality ….
What amazing security does this view give to the whole system of grace, seeing that it cannot fail in a single point except through a schism in the Godhead itself. The hand trembles that writes the daring suggestion; which is only saved from blasphemy by the assurance that he who searches the heart knows it is written only to give the most intense emphasis to the truth which it declares.
Well may the Psalmist of old sweep with his fingers the strings of the Hebrew lyre to the tune of the sixty-second Psalm (vs. 6,7): “He only is my rock and my salvation: he is my defence; I shall not be greatly moved. In God is my salvation and my glory; the rock of my strength and my refuge is in God.”