The Gospel, with its counsels and examples, was to be its true Rule.
The great innovation designed by the Third Order was concord; this fraternity was a union of peace, and it brought to astonished Europe a new truce of God.

Whether the absolute refusal to carry arms[21] was an idea wholly chimerical and ephemeral, the documents are there to prove, but it is a fine thing to have had the power to bring it about for a few years.
The second essential obligation of the Brothers of Penitence appears to have been that of reducing their wants so far as possible, and while preserving their fortunes to distribute to the poor at proper intervals the free portion of the revenue after contenting themselves with the strictly necessary.[22] To do with joy the duties of their calling; to give a holy inspiration to the slightest actions; to find in the infinitely littles of existence, things apparently the most commonplace, parts of a divine work; to keep pure from all debasing interest; to use things as not possessing them, like the servants in the parable who would soon have to give account of the talents confided to them; to close their hearts to hatred, to open them wide to the poor, the sick, to all abandoned ones, such were the other essential duties of the Brothers and Sisters of Penitence.
To lead them into this royal road of liberty, love, and responsibility, Francis sometimes appealed to the terrors of hell and the joys of paradise, but interested love was so little a part of his nature that these considerations and others of the same kind occupy an entirely secondary place in those of his writings which remain, as also in his biographies.
For him the gospel life is natural to the soul.

Whoever comes to know it will prefer it; it has no more need to be proved than the outer air and the light.

It needs only to lead prisoners to it, for them to lose all desire to return to the dungeons of avarice, hatred, or frivolity.
Francis and his true disciples make the painful ascent of the mountain heights, impelled solely, but irresistibly, by the inner voice.

The only foreign aid which they accept is the memory of Jesus, going before them upon these heights and mysteriously living again before their eyes in the sacrament of the eucharist.
The letter to all Christians in which these thoughts break forth is a living souvenir of St.Francis's teachings to the Tertiaries.
To represent these latter to ourselves in a perfectly concrete form we may resort to the legend of St.Lucchesio, whom tradition makes the first Brother of Penitence.[23] A native of a little city of Tuscany he quitted it to avoid its political enmities, and established himself at Poggibonsi, not far from Sienna, where he continued to trade in grain.