The interpretation timeline
2 Timothy 1:3 Douay-Rheims

I give thanks to God, whom I serve from my forefathers with a pure conscience, that without ceasing, I have a remembrance of thee in my prayers, night and day.

A.D. 407 – 1871 5 witnesses 6 excerpts

Patristic

before A.D. 750
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“How then, you will say, were unclean persons considered worthy of the gospel? Because they wished and longed for it. Among these, some, though in error, were attracted to him because they were not made unclean through disordered loves. Then there are others who were not rejected because they sought God of their own accord. In these ways, many even from their ancestors have received the true religion.”
Source
“"I thank God, whom I serve from my forefathers with pure conscience, that without ceasing I have remembrance of thee in my prayers night and day; greatly desiring to see thee, being mindful of thy tears, that I might be filled with joy." "'I thank God,' he says, 'that I remember thee,' so much do I love thee." This is a mark of excessive love, when a man glories in his affection from loving so much. "I thank God," he says, "Whom I serve": and how? "With a pure conscience," for he had not violated his conscience. And here he speaks of his blameless life, for he everywhere calls his life his conscience. Or because I never gave up any good that I purposed, for any human cause, not even when I was a persecutor. Wherefore he says, "I obtained mercy, because I did it ignorantly in unbelief" (1 Tim. i. 13); all but saying, "Do not suspect that it was done of wickedness." He properly commends his own disposition, that his love may appear sincere. For what he says is in fact, "I am not false, I do not think one thing and profess another." So in the book of Acts we read he was compelled to praise himself. For when they slandered him as a seditious man and an innovator, he said in his own defense, "Ananias said to me, The God of our fathers hath chosen thee that thou shouldest know His will, and see that Just One, and shouldest hear the voice of His mouth. For thou shalt be His witness unto all men of what thou hast seen and heard." (Acts xxii. 14, Acts xxii. 15) In the same manner here, that he may not, as if he had been forgetful, have the character of one void of friendship and conscience, he justly praises himself, saying, that "without ceasing I have remembrance of thee," and not simply that, but "in my prayers." That is, it is the business of my prayers, that which I constantly continue to perform. For this he shows by saying, "For this I besought God day and night, desiring to see thee." Mark his fervent desire, the intensity of his love. And again, his humility, how he apologizes to his disciples, and then he shows that it was not on light or vain grounds; and this he had shown us before, but again gives proof of it. "Being mindful of thy tears." It was natural for Timothy, when parting from him, to mourn and weep, more than a child torn away from the milk and from the breast of its mother. "That I may be filled with joy; greatly desiring to see thee." I would not willingly have deprived myself of so great a pleasure, though I had been of an unfeeling and brutal nature, for those tears coming to my remembrance would have been enough to soften me. But such is not my character. I am one of those who serve God purely; so that many strong motives urged me to come to thee. So then he wept. And he mentions another cause, and that of a consolatory kind.”
Source

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“Here begins the epistolary narrative, in which he first fortifies him against present persecutions; secondly, against future dangers to the Church, in chapter III, where *but know this*. Again, first he leads him to persist in preaching, which was then the cause and occasion of persecution; secondly he exhorts him to endure tribulations for the sake of Christ, at *do you therefore*, etc., chapter II. Again, first he recalls the good qualities of Timothy himself; secondly he exhorts him to the use of these good qualities through persistence in preaching, at *through which*, etc.; thirdly he sets himself forward as an example, at *in which I have been appointed a preacher and apostle and teacher*, etc. Again, first he sets forth the affection which he had for Timothy; secondly he sets forth the good qualities of Timothy, which called forth in him an affection of this kind, at *mindful*. The affection is shown through two things, namely through prayer and through desire. And so he gives thanks to God for the affection which he has for Timothy, because it is of charity, and charity is the chief gift; as if he were to say: I reckon that I have obtained grace, in that I have such a sincere affection for you. And he says *to my God*, whom, in a special way, *I serve from my forefathers*, not from carnal parents, since 1 Tim. 1: *Christ came to save sinners, of whom I am the first*; but by a service handed down from my forefathers, namely the patriarchs and prophets, who served God sincerely. And he says, *from my forefathers*, because children more easily imitate paternal perfection, both because they are instructed by them, as Tobias was, and also because they more easily imitate friends. And how do I serve him? *In a pure conscience*; because, as we have in Habakkuk 1, v. 13, *your eyes are pure, O Lord, that they should not see evil, and you cannot look upon iniquity*; 2 Cor. 1, 12: *this is our glory, the testimony of our conscience*. He gives thanks for this, because *without ceasing*, whether by day in prosperity, or by night in adversity, I pray for you. Likewise from desire; so he says *desiring to see you*, namely for the consolation of both. Rom. 1, 11: *for I desire to see you*, etc. Then when he says *mindful*, he shows the good qualities which were in Timothy. And first he recalls his affection toward himself; secondly his faith toward God, at *the remembrance*. He says therefore *mindful of tears*, namely which Timothy shed when he departed from him at Ephesus, ready for martyrdom. Or the tears which he shed in prayers. And this *that I may be filled with joy*, that is, this memory fills me with joy. Phil. 2, 2: *fulfill my joy*, etc. Likewise mindful of faith toward God. He first recalls his faith; secondly he shows that it was handed down from his parents, and not newly acquired. He says therefore *the remembrance*, etc. Faith is necessary for a prelate, who is the guardian of the faith. Heb. 11, 6: *without faith it is impossible to please God*. And he says *unfeigned*, for true faith is through good works. James 2, 18: *show me your faith without works, and I will show you my faith from my works*. 1 Tim. 1, 5: *the end of the commandment is charity*, etc. Wis. 1, 5: *it will flee from what is feigned*, etc. And this is not new, but *it dwelt first in your grandmother Lois*, etc. Acts 16, 1 it is said that he was the son of a Jewish woman. *And I am certain*, either by revelation, or by indications, *that in you also*.”
Source

Post-Reformation

c. 1650 – 1900
1832
A.D.
Adam Clarke Methodist
1762–1832
“Whom I serve from my forefathers - Being born a Jew, I was carefully educated in the knowledge of the true God, and the proper manner of worshipping him. With pure conscience - Ever aiming to please him, even in the time when through ignorance I persecuted the Church. Without ceasing I have remembrance of thee - The apostle thanks God that he has constant remembrance of Timothy in his prayers. It is a very rare thing now in the Christian Church, that a man particularly thanks God that he is enabled to pray for Others. And yet he that can do this most must have an increase of that brotherly love which the second greatest commandment of God requires: Thou shalt love thy neighbor as thyself. It is also a great blessing to be able to maintain the spirit of a pure friendship, especially through a considerable lapse of time and absence. He that can do so may well thank God that he is saved from that fickleness and unsteadiness of mind which are the bane of friendships, and the reproach of many once warm-hearted friends.”
Source
1849
A.D.
1774–1849
“Whom I serve from my forefathers with a pure conscience. That is, have always served and worshipped the one true God, as my forefathers had done, which was true, even when he persecuted the Christians; though this he did not with a pure conscience, but with a false mistaken zeal; and his ignorance could not excuse him, after he might have known Christ. (Witham)”
Source
1871
A.D.
1871
“I thank--Greek, "I feel gratitude to God." whom I serve from my forefathers--whom I serve (Rom 1:9) as did my forefathers. He does not mean to put on the same footing the Jewish and Christian service of God; but simply to assert his own conscientious service of God as he had received it from his progenitors (not Abraham, Isaac, &c., whom he calls "the fathers," not "progenitors" as the Greek is here; Rom 9:5). The memory of those who had gone before to whom he is about to be gathered, is now, on the eve of death, pleasant to him; hence also, he calls to mind the faith of the mother and grandmother of Timothy; as he walks in the faith of his forefathers (Act 23:1; Act 24:14; Act 26:6-7; Act 28:20), so Timothy should persevere firmly in the faith of his parent and grandparent. Not only Paul, but the Jews who reject Christ, forsake the faith of their forefathers, who looked for Christ; when they accept Him, the hearts of the children shall only be returning to the faith of their forefathers (Mal 4:6; Luk 1:17; Rom 11:23-24, Rom 11:28). Probably Paul had, in his recent defense, dwelt on this topic, namely, that he was, in being a Christian, only following his hereditary faith. that . . . I have remembrance of thee--"how unceasing I make my mention concerning thee" (compare Plm 1:4). The cause of Paul's feeling thankful is, not that he remembers Timothy unceasingly in his prayers, but for what Timothy is in faith (Ti2 1:5) and graces; compare Rom 1:8-9, from which supply the elliptical sentence thus, "I thank God (for thee, for God is my witness) whom I serve . . . that (or how) without ceasing I have remembrance (or make mention) of thee," &c. night and day--(See on Ti1 5:5).”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.