Smith's Bible Dictionary
Baptism. It is well known that ablution or bathing was common in most ancient nations as a preparation for prayers and sacrifice or as expiatory of sin. In warm countries, this connection is probably even closer than in colder climates; and hence the frequency of ablution in the religious rites throughout the East. Baptism in the name of the Father, Son and Holy Ghost is the rite or ordinance by which persons are admitted into the Church of Christ. It is the public profession of faith and discipleship.
Baptism signifies -
1. A confession of faith in Christ;
2. A cleansing or washing of the soul from sin;
3. A death to sin and a new life in righteousness.
The mode and subjects of baptism being much-controverted subjects, each one can best study them in the works devoted to those questions. The command to baptize was co-extensive with the command to preach the gospel. All nations were to be evangelized; and they were to be made disciples, admitted into the fellowship of Christ's religion, by baptism. Matthew 28:19.
It appears to have been a kind of transition from the Jewish baptism to the Christian. The distinction between John's baptism and Christian baptism appears in the case of Apollos, Acts 18:26-27, and of the disciples at Ephesus mentioned Acts 19:1-6. We cannot but draw from this history, the inference that in Christian baptism, there was a deeper spiritual significance.
These files are public domain.
Smith, William, Dr. Entry for 'Baptism'. Smith's Bible Dictionary. https://www.studylight.org/dictionaries/eng/sbd/b/baptism.html. 1901.