How to know you are a child of God? That is the question on many minds. Much of the holy Christian church teach that either through good works or some other peering at oneself one can tell if he or she belongs to Jesus. That is dreadful because we are such dismal failures in all we think, say or do. We will either overestimate or underestimate that which we see in ourselves. In fact that sin is one turned in on oneself. So it is highly doubtful that God would want us to check ourselves out for assurance. In a recent Issues Etc. the point was made by Pastor Todd Wilkin that baptism is all about certainty.
1 Peter 3:18 For Christ also suffered once for sins, the righteous for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit, 19 in which he went and proclaimed to the spirits in prison, 20 because they formerly did not obey, when God's patience waited in the days of Noah, while the ark was being prepared, in which a few, that is, eight persons, were brought safely through water.
21 Baptism, which corresponds to this, now saves you, not as a removal of dirt from the body but as an appeal to God for a good conscience, through the resurrection of Jesus Christ, 22 who has gone into heaven and is at the right hand of God, with angels, authorities, and powers having been subjected to him. ESV
Since we are unable to go back in time to the crucifixion and resurrection of Jesus he has instituted the sacrament of baptism in order to know we have the forgiveness of sins. This is upsetting to many who insist that baptism is nothing more than getting wet for Jesus. However, God created water and is quite comfortable using it to deliver the earth from sin as well as those who receive this gift.
Many complain that it is false comfort to look at baptism for assurance. That many will go to hell thinking they are saved which are actually lost. This is not understanding that those who do not believe are the ones under condemnation. If a person does not trust in the death and resurrection of Jesus the baptism does him no good. Neither would a wonderful law/gospel sermon. It would unfortunately fall on deaf ears although faith comes by hearing the words of Christ most definitely.
Hebrews 10:19 Therefore, brothers, since we have confidence to enter the holy places by the blood of Jesus, 20 by the new and living way that he opened for us through the curtain, that is, through his flesh, 21 and since we have a great priest over the house of God, 22 let us draw near with a true heart in full assurance of faith, with our hearts sprinkled clean from an evil conscience and our bodies washed with pure water. ESV
In the name of Jesus. Amen. †