Letter 18: 1. Oh how I wish that I could continually say one thing to you! It is this: Let us shake off the burden of unprofitable cares, and bear only those which are useful.

Augustine to Celestinus — Greetings. 1. There is one thing I wish I could say to you constantly: let us shake off the burden of useless anxieties and carry only those that are worthwhile. I do not know whether anything like complete freedom from worry is possible in this world. I wrote to you but have received no reply. I sent you as many of my books against the Manichaeans as I could in finished, revised form, and you have not yet told me what impression they made on you. Now seems a good time for me to ask for them back and for you to return them. Please do not delay — send them along with a letter. I am eager to know what you are doing with them and what further help you think you may need to mount an effective challenge against that error. 2. Since I know you well, let me ask you to accept and reflect on the following brief observations on a vast subject. There is a nature that is subject to change in both place and time: this is the corporeal, the physical world. There is another nature that cannot change with respect to place but can change with respect to time: this is the spiritual. And there is a third Nature that can be changed neither in place nor in time: this is God. The natures I have called changeable are called creatures; the Nature that is unchangeable is called the Creator. Now, since we affirm the existence of anything only insofar as it persists and is one — unity being the essential condition of all beauty and form — you can readily see the hierarchy. The highest Nature exists in the fullest possible way. The lowest exists but cannot be either blessed or wretched. The intermediate nature — the spiritual — lives in wretchedness when it stoops toward what is lowest, and in blessedness when it turns toward what is highest. The person who believes in Christ does not sink his affections into what is lowest. He is not arrogantly self-sufficient in what is intermediate. And so he is fitted for union and fellowship with what is highest. This is the sum of the life to which we are called, urged, and impelled by holy desire to aspire.

Letter 18 (A.D. 390) To Cœlestinus Augustine Sends Greeting. 1. Oh how I wish that I could continually say one thing to you! It is this: Let us shake off the burden of unprofitable cares, and bear only those which are useful. For I do not know whether anything like complete exemption from care is to be hoped for in this world. I wrote to you, but have received no reply. I sent you as many of my books against the Manichæans as I could send in a finished and revised condition, and as yet nothing has been communicated to me as to the impression they have made on your judgment and feelings. It is now a fitting opportunity for me to ask them back, and for you to return them. I beg you therefore not to lose time in sending them, along with a letter from yourself, by which I eagerly long to know what you are doing with them, or with what further help you think that you require still to be furnished in order to assail that error with success. 2. As I know you well, I ask you to accept and ponder the following brief sentences on a great theme. There is a nature which is susceptible of change with respect to both place and time, namely, the corporeal. There is another nature which is in no way susceptible of change with respect to place, but only with respect to time, namely, the spiritual. And there is a third Nature which can be changed neither in respect to place nor in respect to time: that is, God. Those natures of which I have said that they are mutable in some respect are called creatures; the Nature which is immutable is called Creator. Seeing, however, that we affirm the existence of anything only in so far as it continues and is one (in consequence of which, unity is the condition essential to beauty in every form), you cannot fail to distinguish, in this classification of natures, which exists in the highest possible manner; and which occupies the lowest place, yet is within the range of existence; and which occupies the middle place, greater than the lowest, but coming short of the highest. That highest is essential blessedness; the lowest, that which cannot be either blessed or wretched; and the intermediate nature lives in wretchedness when it stoops towards that which is lowest, and in blessedness when it turns towards that which is highest. He who believes in Christ does not sink his affections in that which is lowest, is not proudly self-sufficient in that which is intermediate, and thus he is qualified for union and fellowship with that which is highest; and this is the sum of the active life to which we are commanded, admonished, and by holy zeal impelled to aspire.

EPISTOLA 18 Scripta inter a. 389 et a. 390. A. reposcit ex Caelestino libros contra Manichaeos (n. 1), genusque triplex naturarum earumque rationes breviter attingit (n. 2).   Augustinus Caelestino Augustinus repetit libros contra Manichaeos. 1. O utinam possem assidue tibi aliquid dicere! Id autem aliquid est, ut curis exueremur inanibus, et curis indueremur utilibus. Nam de securitate nescio utrum quidquam in hoc mundo sperandum sit. Scripsi, nec recepi ulla rescripta. Misi adversum Manichaeos libros, quos paratos et emendatos mittere potui, nec quidquam ex illis iudicii motusque vestri notum mihi factum est. Nunc eos repetere iam me, vos autem restituere convenit. Peto itaque ne differatis eos remittere cum rescriptis, quibus nosse cupio quid de illis geritis, vel adhuc ad illum errorem expugnandum quid armaturae vobis opus esse arbitremini. Naturarum triplex genus. 2. Sane quoniam te novi, accipe hoc quiddam grande et breve. Est natura per locos et tempora mutabilis, ut corpus. Et est natura per locos nullo modo, sed tantum per tempora etiam ipsa mutabilis, ut anima. Et est natura quae nec per locos, nec per tempora mutari potest; hoc Deus est. Quod hic insinuavi quoque modo mutabile, creatura dicitur; quod immutabile, Creator. Cum autem omne quod esse dicimus, in quantum manet dicamus, et in quantum unum est, omnis porro pulchritudinis forma unitas sit: vides profecto in ista distributione naturarum, quid summe sit, quid infime, et tamen sit; qui medie, maiusque infimo, et minus summo sit. Summum illud est ipsa beatitas: infimum, quod nec beatum esse potest, nec miserum: quod vero medium, vivit inclinatione ad infimum, misere; conversione ad summum, beate vivit. Qui Christo credit, non diligit infimum, non superbit in medio, atque ita summo inhaerere fit idoneus: et hoc est totum quod agere iubemur, monemur, accendimur.