It is very hard to give a true account of the principles of these Tunkers as they have not published any system or creed, except what two individuals have put forth ... However, I may assert the following things concerning them from my own knowledge. They are General Baptists in the sense which that phrase bears in Great Britian; but not Arians nor Socinians, as most of their brethren in Holland are. General redemption they certainly hold; and, withall, general salvation; which tenets though wrong are consistent.
They use great plainness of language and dress, like the Quakers; and like them will neither swear nor fight. They will not go to law; nor take interest for the money they lend. They commonly wear their beards; and keep the first day sabbath, except one congregation. They have the Lord's supper with its ancient attendants of love-feasts, washing feet, kiss of charity, and right-hand of fellowship. They anoint the sick with oil for recovery; and use the trine immersion with laying on of hands and prayer, even while the person baptized is in the water; which may easily be done as the party kneels down to be baptized; and continues in that posture till both prayer and imposition of hands be performed.
Their church government and discipline are the same with those of the English Baptists; except that every brother is allowed to stand up in the congregation to speak in a way of exhortation and expounding; and when by these means they find a man eminent for knowledge and aptness to teach, they choose him to be a minister, and ordain him with imposition of hands, attended with fasting and prayer and giving the right hand of fellowship. They also have deacons; and ancient widows for deaconesses; and exhorters; who are licensed to use their gifts statedly. They pay not their ministers unless it be in a way of presents, though they admit their right to pay; neither do the ministers assert the right, esteeming it more blessed to give than to receive. Their acquaintance with the Bible is admirable.
Source: The Brethren in Colonial America, Donald F. Durnbaugh