Found most often in John and Acts, but also used in Mt. 27:55; 28:1; Mk. 3:11; 5:15, 38; 12:41; 15:40, 47; 16:4; Lk. 10:18; 14:29; 21:6; 23:35, 48; 24:37, 39; Heb. 7:4; 1 Jn. 3:17; Rev. 11:11-12, the Greek verb “theoreo” meant “perceive,” “look at,” “observe.”  This term can describe literal sight (Acts 17:16; 20:38) or observation and mental perception (Acts 17:22; 21:20; 1 Jn. 3:17).  In Jn. 20:6, this word “moves beyond the basic meaning of literal seeing of an object to the level of an indication that ‘points to the resurrection’” (Exegetical Dictionary of the New Testament, 2:147, quoting Schnackenburg III, 312).