Speaking in tongues would be an evidence of the Holy Spirit and salvation. But not everyone with the Holy Spirit speaks in tongues.Why would anyone want to take the chance?
The evidence of receiving the Holy Ghost is speaking in tongues.
Act 10:46 For they heard them speak with tongues, and magnify God. Then answered Peter,
Act 10:47 Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we?
The gift of the Holy Ghost is eternal life.
Act 2:38 Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.
Rom 6:23 For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
See 1 Corinthians 12.
1 Corinthians 12:30 NASB - 30 All do not have gifts of healings, do they? All do not speak with tongues, do they? All do not interpret, do they?