The Necessity of Good Works
There can be no doubt about the necessity of good works properly understood. They cannot be regarded as necessary to merit salvation, nor as a means to retain a hold on salvation, nor even as the only way along which to proceed to eternal glory, for children enter salvation without having done any good works. The Bible does not teach that no one can be saved apart from good works. At the same time good works necessarily follow from the union of believers with Christ. “He that abideth in me and I in him, the same beareth much fruit,” John 15:5. They are also necessary as required by God, Rom 7:4; 8:12.13; Gal. 6:2, as the fruits of faith, Jas. 2:14, 17, 20-22, as expressions of gratitude. I Cor. 6:20, unto the assurance, of faith, II Peter 1:5-10, and to the glory of God, John 15:8; I Cor. 10:31. The necessity of good works must be maintained over against the Antinomians, who claim that, since Christ not only bore the penalty of sin, but also met the positive demands of the law, the believer is free from the obligation to observe it, an error that is still with us today in some of the forms of dispensationalism. This is a thoroughly false position, for it is only the law as a system of penalty and as a method of salvation that is abolished in the death of Christ. The law as the standard of our moral life is a transcript of the holiness of God and is therefore of permanent validity also for the believer, though his attitude to the law has undergone a radical change. He has received the Spirit of God, which is the Spirit of obedience, so that, without any constraint, he willingly obeys the law. Strong sums it up well, when he says: Christ frees us “(1) from the law as a system of curse and penalty; this He does by bearing the curse and penalty Himself… ; (2) from the law with its claims as a method of salvation; this He does by making His obedience and merits ours… ; (3) from the law as an outward and foreign compulsion; this He does by giving us the spirit of obedience and Sonship, by which the law is progressively realized within.” 
– Louis Berkhof, Systematic Theology, p. 543
1. Syst. Theo., p. 876.