I do not have much on Abijah Adams and Mary Baker, but from these three source's, there is the following entries.
Adams of Massachusetts Author: Herbert F. Adams Call Number: CS71.A198 pg 6 ABIJAH s/o JOHN & MARRY FLAGG, b 1/3/1722 Lexington*, m MARY BAKER 1/19/1742/3 Waltham*
Genealogies of the Families and Descendants of the Early Settlers of Watertown, Massachusetts, Including Waltham and Weston Author: Henry Bond Call Number: R929.1 B71 v.1 pg 1 30 4. Abijah, b. Jan. 3, 1722-3, of Lex.; m., Jan. 19, 1742-3, Mary Baker, of Waltham. Chil., 1. Mary, bap. in Waltham, Jan. 13, 1745; 2. Sarah, bap. Dec. 13, 1747; 4. Joseph, bap. Mar. 3, 1749.
Lexington Vital Records Author: no author Call Number: F74.L671L6 pg 1 18 Abijah, s. of John & Mary (Flagg), b. Jan. 3, 1722, bp. June 23, 1723 pg 94 * Abijah, of Lex., m., in Waltham, Mary Baker, of Waltham, Jan. 19, 1742-43.
My Adams connection is through Abijah'sbrother Mephibosheth. Hope this helps.