If anyone considers himself religious and yet does not keep a tight rein on his tongue, he deceives himself and his religion is worthless.
That's like saying... ... . Okay, before I get to that, what is religious?
Religious: extremely scrupulous(extreme care and great effort) and conscientious(extreme care and great effort)
So basically, being religious is having extreme care about God and putting in great effort to please God.
Back to James 1:26, if we cannot control our tongue, then our extreme care and great effort in relation to God is worthless.
I don't know about you, but that hits me bad... like very bad.
Just as I was typing this post, I snapped at someone and did not control my tongue, now I'm going to ask God for forgiveness about that... (I actually just prayed for a couple of seconds).
That being said, it's like James is saying there's no hope because we all do it sometimes, I mean, none of us is close to being perfect... that's where Grace comes in, amazing grace from God.
James 4:6 says But He(God) gives us even more grace to stand against such evil desires
That's it... I don't think we could ask for more...
We have grace to resist such temptations to snap and let our tongue loose, and even if we mess up sometimes, don't worry, we have a very very Holy but merciful God who is faithful and just to forgive all our sins(1 John 1:9).
Hope that's useful to you somehow.