To Timothy, my dearly beloved son
Not in a natural, but in a spiritual sense; and not on account of his being an instrument of his conversion, but by reason of that instruction in the doctrines of the Gospel which he gave him, it being usual to call disciples children; and he calls him so, because as a son, he, being young in years, served with him, and under him, as a father, in the Gospel of Christ; for whom he had a very great affection, on account of his having been a companion with him in his travels, and very useful to him in the ministry, and because of his singular and eminent gifts, great grace, religion, and holiness: Grace, mercy, and peace (See Gill on 1 Timothy 1:2).