If Christians know not with this knowledge, they walk in the world as if they were pinioned; or as if fetters were hanged on their heels. But this enlarged their steps under them (2 Sam 22:37): by the knowledge of this love they may walk at liberty, and their steps shall not be straitened. This is that which Solomon intends when he saith, "Get wisdom, and get understanding" (Prov 4:5). Then "when thou goest, thy steps shall not be straitened, and when thou runnest, thou shalt not stumble" (Prov 4:12). A man that has only from hand to mouth, is oft put to it to know how to use his penny, and comes off also, many times, but with an hungry belly; but he that has, not only that, but always over and to spare, he is more at liberty, and can live in fullness, and far more like a gentleman. There is a man has a cistern, and that is full of water: there is another also, that has his cistern full, and withal, his spring in his yard; but a great drought is upon the land in which they dwell: I would now know, which of these two have the most advantage to live in their own minds at liberty, without fear of wanting water? Why this is the case in hand. There is a Christian that knows Christ in all those degrees of his love that are knowable, but he knoweth Christ nothing in his love that passeth knowledge. There is another Christian, and he knows Christ, as the first, but withal, he also knows him as to his love that passeth knowledge. Pray now tell me, which of these two are likeliest to live most like a Christian, that is, like a spiritual prince, and like him that possesseth all things? which has most advantage to live in godly largeness of heart, and is most at liberty in his mind? which of these two have the greatest advantage to believe, and the greatest engagements laid upon him to love the Lord Jesus? which of these have also most in readiness to resist the wiles of the devil, and to subdue the power and prevalency of corruptions? 'Tis this, that makes men fathers in Christianity. "I write unto you, fathers, because ye have known;—I have written unto you, fathers, because ye have known" (1 John 2:13-14), why, have not others known, not so as the fathers? The fathers have known and known. They have known the love of Christ in those degrees of love which are knowable, and have also known the love of Christ to be such which passeth knowledge. In my father's house is bread enough and to spare, was that that fetched the prodigal home (Luke 15:17). And when Moses would speak an endless all to Israel, for the comfort and stay of their souls, he calls their God, "The fountain of Jacob upon a land of corn and wine" (Deu 33:28).
(3.) By this knowledge, or knowing of the love of Christ which passeth knowledge, there is begot in Christians a greater desire to press forwards to that which is before them (Phil 3:12-21). What is the reason of all that sloth, carnal contentedness, and listlessness of spirit in Christians, more than the ignorance of this. For he that thinks he knows what can be known, is beyond all reason that should induce him to seek yet after more. Now the love of Christ may be said, not to be knowable, upon a threefold account: [namely]. For that my knowledge is weak. For that my knowledge is imperfect. Or for that, though my knowledge be never so perfect, because the love of Christ is eternal.
There is love that is not to be apprehended by weak knowledge. Convince a man of this, and then, if the knowledge of what he already has, be truly sweet to his soul (Prov 2:10), it will stir him up with great heartiness to desire to know what more of this is possible.
There is love beyond what he knows already, who is indued with the most perfect knowledge, that man here may have. Now if what this man knows already of this love is indeed sweet unto him; then it puts him upon hearty desires that his soul may yet know more. And because there is no bound set to man, how much he may know in this life thereof; therefore his desires, notwithstanding what he has attained, are yet kept alive, and in the pursuit after the knowledge of more of the love of Christ. And God in old time has taken it so well at the hands of some of his, that their desires have been so great, that when, as I may say, they have known as much on earth as is possible for them to know; (that is by ordinary means) he has come down to them in visions and revelations; or else taken them up to him for an hour or two into paradise, that they might know, and then let them down again.
But this is not all, There is a knowledge of the love of Christ, that we are by no means capable of until we be possessed of the heavens. And I would know, if a man indeed loveth Christ, whether the belief of this be not one of the highest arguments that can be urged, to make such an one weary of this world, that he may be with him. To such an one, "to live is Christ, and to die is gain" (Phil 1:21-23). And to such an one, it is difficult to bring his mind to be content to stay here a longer time; except he be satisfied that Christ has still work for him here to do.
I will yet add, There is a love of Christ, I will not say, that cannot be known, but I will say, that cannot be enjoyed; no, not by them now in heaven (in soul) until the day of judgment. And the knowledge of this, when it has possessed even men on earth, has made them choose a day of judgment, before a day of death, that they might know what is beyond that state and knowledge which even the spirits of just men made perfect, now do enjoy in heaven (2 Cor 5:4). Wherefore, as I said at first, To know the love of Christ that passeth knowledge, is advantageous upon this account; it begetteth in Christians a great desire to reach, and press forward to that which is before.
One thing more, and then, as to this reason, I have done. Even that love of Christ that is absolutely unknowable, as to the utmost bound thereof because it is eternal, will be yet in the nature of it sweet and desirable, because we shall enjoy or be possessed of it so. This therefore, if there were no more, is enough, when known, to draw away the heart from things that are below, to itself.
(4.) The love that passeth knowledge. The knowledge of that is a very fruitful knowledge. It cannot be, but it must be fruitful. Some knowledge is empty, and alone, not attended with that good, and with those blessings wherewith this knowledge is attended. Did I say, it is fruitful? I will add, it is attended with the best fruit; it yieldeth the best wine: It fills the soul with all the fullness of God. "And to know the love of Christ which passeth knowledge, that ye may be filled with all the fullness of God." God is in Christ, and makes himself known to us by the love of Christ. "Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God," for God is not to be found nor enjoyed, but in him, consequently, he that hath, and abideth in the doctrine of Christ, "hath both the Father and the Son" (2 John 9). Now, since there are degrees of knowledge of this doctrine, and since the highest degree of the knowledge of him, is to know that he has a Love that passeth knowledge, it follows, that if he that has the least saving knowledge of this doctrine, hath God; he that hath the largest knowledge of it, has God much more, or, according to the text, is filled with all the fullness of God. What this fullness of God should be, is best gathered from such sayings of the Holy Ghost, as come nearest to this, in language, filled,
Full of goodness (Rom 15:14).
Full of faith (Acts 6:5).