The harmony spoken of in Romans 5:5 is only indirectly connected to the imperative to accept those who are weak in the faith. Romans 14:1–23, after all, did not address the issues of division or strife per se, but only the care for the anxious and the weak. Lovingly interacting with the weak in faith is essential for the unity of the church, however, since the harmony mentioned here can only come about when Christians, together as one, address the weaknesses of the powerless. Christianity derives its outward strength from the unity of the praise and worship within the church itself. Without that unanimity in faith, hope, and love, the church loses her strength, meaning she can no longer help and support the unbelieving and powerless of this world.1
5 May the God of endurance and encouragement grant you to live in such harmony with one another, in accord with Christ Jesus,