Just to keep this post at a visually reasonable length, I'm going to post the lists of verses - with some introductory comments - and then comment in a further post (posts?).
I get to mention a site I use frequently, http://www.biblestudytools.com/, which has many useful Bible study tools – and that is its name, Bible Study Tools. It's part of Crosswalk.com, and is free. Users have access to the equivalent of a library worth possibly several hundred dollars. First of all, it has more than 20 English Bible translations, as well as several other languages (including French, Spanish, Italian and German). The search function allows the user to search for any word or phrase in whatever translation is chosen, or for a particular verse or chapter. At least two English translations – the King Lames Version and the New American Standard Bible – also have a feature that allows the user to select and see the Hebrew or Greek words used in a verse, and the definitions of the words. Further, the user can also see every time a particular Hebrew or Greek word is used. If it isn't obvious, I've used the search function and lexicon features quite a bit in this series of posts. In this post I will be using the feature that allows one to see every place particular Greek words are used, specifically, baptizo, baptisma and baptismos (baptizo, baptisma and baptismos). Once I have those lists, I will reorganize the lists of verses according to: who is baptized (or what is washed); by whom; in what. This will let us see what baptisms are spoken of in the New Testament, and possibly understand the “one baptism” spoken of in Ephesians 4:5.
I am not a theologian or anything like that. What I want to do here is to let Scripture speak for itself. I've described how I will select relevant data and how I will sort it so that any reader who wants to may duplicate what I did, using the Bible Study Tools website or by using a resource such as Englishman's Greek Concordance in conjunction with a Strong's Concordance. I don't claim to have anything like complete knowledge of the Bible, or even of this subject. So I'm very ready to learn how I may be missing or misunderstanding what Scripture has to say and thereby improve my understanding of Scripture.
First, the lists for the three Geek words:
baptizo
Matthew 3:6; Matthew 3:11; Matthew 3:13-14; Matthew 3:16; Matthew 28:19; Mark 1:4-5; Mark 1:8-9; Mark 6:14; Mark 6:24; Mark 10:38-39; Mark 16:16; Luke 3:7; Luke 3:12; Luke 3:16; Luke 3:21; Luke 7:29-30; Luke 11:38; Luke 12:50; John 1:25-26; John 1:28; John 1:31; John 1:33; John 3:22-23; John 3:26; John 4:1-2; John 10:40; Acts 1:5; Acts 2:38; Acts 2:41; Acts 8:12-13; Acts 8:16; Acts 8:36; Acts 8:38; Acts 9:18; Acts 10:47-48; Acts 11:16; Acts 16:15; Acts 16:33; Acts 18:8; Acts 19:3-5; Acts 22:16; Romans 6:3; 1 Corinthians 1:13-17; 1 Corinthians 10:2; 1 Corinthians 12:13; 1 Corinthians 15:29; Galatians 3:27
baptisma
Matthew 3:7; Matthew 21:25; Mark 1:4; Mark 10:38-39; Mark 11:30; Luke 3:3; Luke 7:29; Luke 12:50; Luke 20:4; Acts 1:22; Acts 10:37; Acts 13:24; Acts 18:25; Acts 19:3-4; Romans 6:4; Ephesians 4:5; Colossians 2:12; 1 Peter 3:21
baptismos
Mark 7:4; Hebrews 6:2; Hebrews 9:10
And now, the baptisms or washings to which each verse refers:
Jewish Ceremonial Washings: things are washed by observant Jews in water
Mark 7:4; Luke 11:38; Hebrews 9:10
John's Baptism: Penitents are baptized by John (or one of John's disciples) in water
Matthew 3:6, 7, 11 (first use), 13-14, 16; Matthew 21:25; Mark 1:4-5, 9; Mark 6:14, 24; Mark 11:30; Luke 3:3, 7, 12, 21; Luke 7:29-30; Luke 20:4; John 1:25-26, 28, 31; John 3:23; John 10:40; Acts 1:22; Acts 10:37; Acts 11:16 (first use); Acts 13:24; Acts 18:25; Acts 19:3-4
Baptism into the Body of Christ: Believers are baptized by the Holy Spirit into the Body of Christ
Romans 6:3 (?); 1 Corinthians 12:13; Galatians 3:27
Christian Water Baptism: Believers are baptized by other believers in water
Matthew 28:19; Mark 16:16; Acts 2:38, 41; Acts 8:12-13, 16, 36, 38; Acts 9:18; Acts 10:47-48; Acts 16:15, 33; Acts 18:8; Acts 19:5; Acts 22:16; Romans 6:3 (?), 4; 1 Corinthians 1:14-17; Colossians 2:12; 1 Peter 3:21
Baptism in the Spirit: Believers are baptized by Jesus baptized in the Holy Spirit
Matthew 3:11 (second use); Mark 1:8; Luke 3:16; John 1:33; Acts 1:5; Acts 11:16 (second use)
Other or Uncertain: The verse refers to something else or is not specific
Mark 10:38-39 (a metaphor for Jesus' sufferings); Luke 12:50 (similar to Mark 10); John 3:22, 26, 4:1-2 (Jesus' disciples baptized penitents); 1 Corinthians 1:13 (Paul arguing against loyalty to human teachers causing divisions among believers); 1 Corinthians 10:2 (baptism as a metaphor for an event in Jewish history); 1 Corinthians 15:29 baptism for the dead (I do not understand this); Ephesians 4:5; Hebrews 6:2