Christian devotedness founded on the truth and produced by the power of the Spirit: I believe it to be of the utmost importance for saints and for the testimony of God. Surely, doctrine is of deep importance. But the expression of the power of [doctrine] in the heart will manifest itself in devotedness.
As a general rule, Christians (apart from a special call of God) should abide in the same calling wherein they are called (1 Cor. 7:2020Let every man abide in the same calling wherein he was called. (1 Corinthians 7:20)). It is here that the motives and character of our walk are summed up in one word—Christ. “To me,” says the Apostle, “to live is Christ.” He is both the life and the motive of life, giving character to our walk.
The spring and source of all true devotedness is divine love filling and operating in our hearts. Paul says “the love of Christ constraineth us” (2 Cor. 5:1414For the love of Christ constraineth us; because we thus judge, that if one died for all, then were all dead: (2 Corinthians 5:14)). Christian devotedness casts away what does not glorify Christ.
J. N. Darby (from Collected Writings, Vol. 16)