1 Timothy 3:9

Holding the mystery of the faith
The doctrine of the Gospel, called the "faith", because it contains things to be believed; proposes Christ the object of faith; is the means by which faith comes, and is unprofitable without it: it is called "the mystery", because it is of divine revelation, and could have never been discovered by human reason; and now it is revealed, the modus of many things contained in it remains a mystery; several of the doctrines of it are mysterious ones, particularly the doctrine of the Trinity; and which the ancient Jews call by this very name, ^F1 (atwnmyhmd azr) , "the mystery of faith"; the incarnation of the Son of God, the union of the saints to Christ, and their communion with him, and the resurrection of the dead, with others. Now this mysterious doctrine of faith is to be held by deacons; they are to profess it, and to hold fast the profession of it and that

in a pure conscience;
with a conscience sprinkled by the blood of Christ; with a conscience void of offence both towards God and man; with a suitable life and conversation; a conversation becoming the Gospel of Christ, and by which it is adorned: and this part of their character is necessary, that such may be able to instruct and establish those who are weak in the faith, and oppose and refute the erroneous, and also recommend the Gospel by their own example; otherwise should their principles or practices be bad, their influence on others might be very pernicious and fatal.