Joining a third order is not the same as joining a regular parish group.
First, I would like to point out that it is possible to grow in holiness without joining a secular third order. Joining a lay order should be approached with the same level of prayerful discernment as if you were joining any religious order — in fact, that is precisely what you would be doing — and should be done under the direction of a spiritual director. It is not a matter of “choosing” but of discerning one’s vocation. Joining a third order is not the same as joining a regular parish group; there are vows that are taken and Rules and Constitutions each order lives by. You are deciding to embrace a religious discipline. That’s a very serious thing to consider.
If you just want accountability, or a group of fellow Catholics to pray with, you might be better served joining a group at a parish level. This isn’t to discourage you from your attempts at spiritual growth. On the contrary, this is to help you avoid that spiritual pitfall of not living up to your own expectations. We often find good people trying to be the perfect, holiest Catholic they can, only to be defeated by their own shortcomings. Again, let me be clear: a third order is a vow to live a religious discipline similar to that of a monk, friar, or nun. It is not something most of us might be called to.
Joining a third order is also not the only way in which laity can practice and grow in holiness.
- If you have a family you can make your home a domestic church and involve everyone in the household. Charity and good works often start within in our own homes.
- Be an ethical employee who isn’t idle and doesn’t participate in gossip. You don’t have to hang icons all about your workspace (some companies may have policies against religious displays) but you can start each work day with a Rosary on your commute and a promise to devote all your work as prayer of thanksgiving for being gainfully employed.
- Make a morning offering, an evening examen, and say grace before each meal.
- Attend daily Mass when available.
- Make regular use of the sacrament of Reconciliation.
These things in themselves will help you become a more disciplined, mindful, and prayerful Catholic. I would suggest you start there for awhile, and seek guidance from a spiritual director to discern your vocation, and help you identify which community you might be best suited for, if you are indeed called to join a secular order.