"Water Baptism"
While I certainly understand that some manage to not see a reference to Baptism here, the denial that this "washing" is not a reference to "water baptism" because it is "supernatural act of the Holy Spirit" and is "by grace, not any act or procedure we might perform" is at best a caracture of the views of the many people who have seen this as a reference to Baptism. A quick check of some other comentaries in my libary shows that the Oxford Biblical Commentary sees it as a reference to Baptism, as does Lange and Hermeneia (Debelius/Cunzelmann). Even Towner in IVP NT Commentary is much more helpful and fair to those of us in Liturgical traditions who say that Baptism is God's act...
Titus 3:5Faithlife Study Bible
3:5 because of his mercy See 2 Tim 1:9 and note. Eleos EDNT regeneration Refers to the transformation of the corrupt human nature by the Holy Spirit. Jesus described salvation in similar terms, emphasizing God’s radical work within a person (John 3:3, 5, 8). Through the work of the Holy Spirit, believers experience a rebirth from a state of spiritual death (compare Eph 2:1–6; Col 2:13). The presence of the Spirit enables them to live in a manner that pleases God (compare Rom 8:6–8). The washing here denotes an inner, spiritual