97. "If brothers dwell together, and one of them die, and have no child...her husband's brother shall go in to her, and take her to him to wife" (Devarim 25:5). This precept is to marry one's brother's widow, since a brother's widow is Dalet OF ONE (HEB. ECHAD, ALEPH CHET DALET), and together with Aleph Chet OF ECHAD it is one. THAT IS, THE BROTHER (HEB. ACH, ALEPH CHET) SHOULD MEDITATE ON THIS UNIFYING. And if, heaven forbid, THE BROTHER does not with a WHOLE heart wish to bring Aleph Chet to Dalet, THE DALET being the wife and mate of the brother, BUT CONCENTRATE ON HIS OWN PLEASURE, he creates a separation and brings Samael, another El, in between. It says of him "that he spilled it on the ground..." (Beresheet 38:9). THEN the tip is gone from the letter Dalet of Echad AND IT TURNS INTO RESH; AND THE WORD ECHAD BECOMES ACHER (ENG. 'OTHER'). This is why, "and it came to pass, when he went in to his brother's wife, that he spilled it on the ground, lest he should give seed to his brother" (Ibid.). Spilling seed in vain withholds many blessings from one, and IT BRINGS separation to union. This is why, "And Er, Judah's firstborn, was wicked in the sight of Hashem; and Hashem slew him" (Ibid. 7).