Matthew Henry on 1 Chronicles 6

We have an account of Levi in this chapter. The priests and Levites were more concerned than any other Israelites, to preserve their descent clear, and to be able to prove it; because all the honours and privileges of their office depended upon their descent. Now, the Spirit of God calls ministers to their work, without any limit as to the families they came from; and then, as now, though believers and ministers may be very useful to the church, none but our great High Priest can make atonement for sin, nor can any be accepted but through his atonement.