If by "works" you mean works of obedience to God then yes on must go on to live an obedient life as stated in this position paper by the Missionary Church, USA.
Position Papers – Missionary Church USA
It was a little confusing on their website to emphasize speaking in tongues on the main page (among the other topics). It should be asked as a question instead of it being made as a statement.
I skimmed their article on this point, so I misunderstood their statement of faith on tongues. So my apologies. They appear to be open to the idea of speaking in tongues, but they do not see it as evidence of the fulness of the Spirit.
Their statement of faith says:
"So while we recognize the gifts of the Holy Spirit as taught in Scripture to be valid gifts for the church today, no particular gift or gifts are the necessary or required evidence of the fullness of the Holy Spirit, nor are they considered as the evidence of Christian maturity."
Where I disagree with them on is this part:
"Speaking in tongues is referred to in scripture both in corporate and private worship."
I believe 1 Corinthians 14 is teaching corporate prayer only and not both corporate and private prayer.
So do they encourage praying in tongues in private? I do not know that answer. If they do, I do not think that is biblical.
They do not believe in Cessationism (like myself), but they appear to be open to being Charismatic but they are not practicing Charimatic church that I am aware of. I am 1% open that I could be wrong about Cessationism (For I do not want to speak against God, just in case I am wrong; But I lean towards Cessationism, because there are many verses that suggest it, and what miracles we see in the churches today is not like what we read about in the early church).
Sorry, I do not mean to be overly critical, it is just that I tend to be more cautious (than accepting) in these last days. For more times than I can count, I have been disappointed by other believers in what they believe, teach and practice. They appear to be a fine church, but I would disagree with them if they encouraged private speaking in tongues.