One thing that sets Mormons apart is that when someone is interested in the church, their Mormon friends will tell them to pray and ask God if it is true. Some groups that try to prevent people from converting try to talk people out of doing 
that—for good reason. If you ask God what is true, and He tells you, then, if you love God, you’ll do as He asks and you don’t want people doing that unless you’re sure you’ve found the truth. Those groups will try to convince you there is no way to know who is answering your prayer, but Mormons, believing in the Bible, know that isn’t true. After all, the Bible promises we can receive answers to our questions from God:
“And whatsoever ye shall ask in my name, that will I do, that the Father may be glorified in the Son. If ye shall ask any thing in my name, I will do it.” John 14:13-14.
“Ye have not chosen me, but I have chosen you, and ordained you, that ye should go and bring forth fruit, and that your fruit should remain: that whatsoever ye shall ask of the Father in my name, he may give it you.” John 15:16.
And in that day ye shall ask me nothing. Verily, verily, I say unto you, Whatsoever ye shall ask the Father in my name, he will give it you. Hitherto have ye asked nothing in my name: ask, and ye shall receive, that your joy may be full. John 16:23-24.
If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him (James 1:5).
The Bible never warns us not to pray—it specifically instructs us to do so, even if all we want is wisdom. It promises to give us the wisdom we seek, and so those who try to talk you out of praying are teaching contrary to the Bible.
Why does praying for a testimony matter so much? To most people, choosing a church means visiting a lot of different faiths and then choosing the one that most closely fits what you already believe. While many potential Mormons do discover The Church of Jesus Christ of Latter-day Saints teaches what they believe, they are still told that just isn’t enough. It isn’t enough to find a church that believes what you hope is true—you need to know what really is true. Only God can tell you that.
If a situation arose that seemed to prove the church false, some people—those without real testimonies—might leave the church. Most, however, would continue to attend their meetings, carry out their church work, and live the gospel. Why would they do that? It is because their testimony isn’t based on facts, although facts and evidence exist for some aspects of the gospel. Their testimony comes directly from God and they trust God. They would know that whatever facts might seem to work against them, God would take care of it and the so-called evidence would be proven false. It isn’t blind faith. It is personally-proven faith.
A person who has prayed and knows without question the church is true is unshakable. He will not be swayed by fashion or clever arguments. In the Bible, we read of many who tried to trap or disprove the Savior through clever questions, arguments, and evidence, but none prevailed. Jesus knew who He was and His true followers knew as well. In the end, it is the Holy Ghost, not secular arguments, that prove the truth of God’s gospel.