Many have said that they receive God's promise by faith. Then they go on to say, "I don't need evidence," but they forget that unless faith brings forth evidence, it is not faith. Faith without works is dead (James 2:17). For someone to say, "I receive the Holy Ghost by faith" means that he shall bring forth the evidence accompanying the baptism of the Holy Ghost. Remember, Peter said he knew the members of Cornelius's household had received the Holy Ghost because he heard them speak with tongues and magnify God (Acts 10:45,46). Are men today more spiritual than Peter? Can they know by faith what Peter knew by what he heard?
No, the evidence has not changed, but man's heart has grown colder. God has chosen the foolishness of this world to confound the wise; and God has chosen the weak things of the world to confound the things which are mighty (I Corinthians 1:27). Paul tells us in I Corinthians 14:2 that "he that speaketh in an unknown tongue speaketh not unto men, but unto God: for no man understandeth him; howbeit in the Spirit he speaketh mysteries." Paul in I Corinthians 14 is not doing away with tongues, but merely giving the order of usage in the church. He goes on to say in verses 20-22, "Brethren, be not children in understanding: howbeit in malice be children, but in understanding be men."
He then goes on to tell us what Isaiah 28:11 says, "In the law it is written, 'With men of other tongues and other lips will I speak unto this people: and yet for all that will they not hear me, saith the Lord.' Wherefore tongues are for a sign, not to them that believe, but to them that believe not; but prophesying serveth not for them that believe not, but for them which believe." This tells us that tongues are a sign, a witness against them that do not believe. Tongues are the evidence to those who obey and believe God's promise.