Frequent references are found in Scripture to,
1) Mourning for the dead. Abraham mourned for Sarah (Gen. 23:2); Jacob for Joseph (37:34, 35); the Egyptians for Jacob (50:3-10); Israel for Aaron (Num. 20:29), for Moses (Deut. 34:8), and for Samuel (1 Sam. 25:1); David for Abner (2 Sam. 3:31, 35); Mary and Martha for Lazarus (John 11); devout men for Stephen (Acts 8:2), etc.
2) For calamities, Job (1:20, 21; 2:8); Israel (Ex. 33:4); the Ninevites (Jonah 3:5); Israel, when defeated by Benjamin (Judg. 20:26), etc.
3) Penitential mourning, by the Israelites on the day of atonement (Lev. 23:27; Acts 27:9); under Samuel's ministry (1 Sam. 7:6); predicted in Zechariah (Zech. 12:10, 11); in many of the psalms (51, etc.).
Mourning was expressed, (1) by weeping (Gen. 35:8, marg.; Luke 7:38, etc.); (2) by loud lamentation (Ruth 1:9; 1 Sam. 6:19; 2 Sam. 3:31); (3) by the disfigurement of the person, as rending the clothes (Gen. 37:29, 34; Matt. 26:65), wearing sackcloth (Gen. 37:34; Ps. 35:13), sprinkling dust or ashes on the person (2 Sam. 13:19; Jer. 6:26; Job 2:12), shaving the head and plucking out the hair of the head or beard (Lev. 10:6; Job 1:20), neglect of the person or the removal of ornaments (Ex. 33:4; Deut. 21:12, 13; 2 Sam. 14:2; 19:24; Matt. 6:16, 17), fasting (2 Sam. 1:12), covering the upper lip (Lev. 13:45; Micah 3:7), cutting the flesh (Jer. 16:6, 7), and sitting in silence (Judg. 20:26; 2 Sam. 12:16; 13:31; Job 1:20).
In the later times we find a class of mourners who could be hired to give by their loud lamentation the external tokens of sorrow (2 Chr. 35:25; Jer. 9:17; Matt. 9:23).
The period of mourning for the dead varied. For Jacob it was seventy days (Gen. 50:3); for Aaron (Num. 20:29) and Moses (Deut. 34:8) thirty days; and for Saul only seven days (1 Sam. 31:13). In 2 Sam. 3:31-35, we have a description of the great mourning for the death of Abner.