To Mrs. Wilberforce. 
September 1764. 

My Dear Madam, —Your welfare I rejoice in; your warfare I understand something of. St. Paul describes his own case in a few words, "Without were fightings, within were fears." Does not this comprehend all you would say? And how are you to know experimentally either your own weakness or the power, wisdom, and grace of God, seasonably and sufficiently afforded, but by frequent and various trials? How are the graces of patience, resignation, meekness, and faith, to be discovered and increased, but by exercise? The Lord has chosen, called, and armed us for the fight; and shall we wish to be excused? Shall we not rather rejoice that we have the honour to appear in such a cause, under such a Captain, such a banner, and in such company? A complete suit of armour is provided, weapons not to be resisted, and precious balm to heal us if haply we receive a wound, and precious ointment to revive us when we are in danger of fainting. Further, we are assured of the victory beforehand; and oh, what a crown is prepared for every conqueror, which Jesus, the righteous Judge, the gracious Saviour, shall place upon every faithful head with his own hand! Then let us not be weary and faint, for in due season we shall reap. The time is short; yet a little while, and the struggle of indwelling sin, and the contradiction of surrounding sinners, shall be known no more. You are blessed, because you hunger and thirst after righteousness. He whose name is Amen has said you shall be filled. To claim the promise is to make it our own; yet it is becoming us to practise submission and patience, not in temporals only, but also in spirituals. We should be ashamed and grieved at our slow progress, so far as it is properly chargeable to our remissness and miscarriage; yet we must not expect to receive everything at once, but wait for a gradual increase; nor should we forget to be thankful for what we may account a little, in comparison of the much we suppose others have received. A little grace, a spark of true love to God, a grain of living faith, though small as mustard-seed, is worth a thousand worlds. One draught of the water of life gives interest in and earnest of the whole fountain. It becometh the Lord's people to be thankful; and to acknowledge his goodness in what we have received, is the surest as well as the pleasantest method of obtaining more. Nor should the grief, arising from what we know and feel of our own hearts, rob us of the honour, comfort and joy, which the word of God designs us, in what is there recorded of the person, offices, and grace of Jesus, and the relations He is pleased to stand in to his people. Though the believer is nothing in himself, yet having all in Jesus, he may rejoice in his name all the day. The Lord enable us so to do. The joy of the Lord is the strength of his people: whereas unbelief makes our hands hang down, and our knees feeble, dispirits ourselves, and discourages others; and though it steals upon us under a semblance of humility, it is indeed the very essence of pride. By inward and outward exercises, the Lord is promoting the best desire of your heart, and answering your daily prayers. Would you have assurance? The true solid assurance is to be obtained no other way. When young Christians are greatly comforted with the Lord's love and presence, their doubts and fears are for that season at an end. But this is not assurance; so soon as the Lord hides his face, they are troubled, and ready to question the very foundation of hope. Assurance grows by repeated conflict, by our repeated experimental proof of the Lord's power and goodness to save; when we have been brought very low and helped, sorely wounded and healed, cast down and raised again, have given up all hope, and been suddenly snatched from danger, and placed in safety; and when these things have been repeated to us and in us a thousand times over, we begin to learn to trust simply to the word and power of God, beyond and against appearances; and this trust, when habitual and strong, bears the name of assurance; for even assurance has degrees. 

You have good reason, madam, to suppose that the love of the best Christians to an unseen Saviour is far short of what it ought to be. If your heart be like mine, and you examine your love to Christ by the warmth and frequency of your emotions towards him, you will often be in a sad suspense, whether or not you love him at all. The best mark to judge by, and which He has given us for that purpose, is to inquire if his word and will have a prevailing, governing influence upon our lives and temper. If we love him, we do endeavour to keep his commandments; and it will hold the other way; if we have a desire to please him, we undoubtedly love him. Obedience is the best test; and when, amidst all our imperfections, we can humbly appeal concerning the sincerity of our view, this is a mercy for which we ought to be greatly thankful. He that has brought us to will, will likewise enable us to do according to his good pleasure. I doubt not but the Lord whom you love, and on whom you depend, will lead you in a sure way, and establish, and strengthen, and settle you in his love and grace. Indeed, He has done great things for you already. 

As to daily occurrences, it is best to believe that a daily portion of comforts and crosses, each one the most suitable to our case, is adjusted and appointed by the hand which was once nailed to the cross for us; that where the path of duty and prudence leads, there is the best situation we could possibly be in at that juncture. We are not required to afflict ourselves immoderately for what is not in our power to prevent, nor should anything that affords occasions for mortifying the spirit of self be accounted unnecessary. 
I am, my dear madam, 
Your obliged and affectionate servant, 
John Newton.