Reference for Moed Katan 55:15

בי רב חסדא סמידא לכלבי ולא מתבעי בי רבה נהמא דשערי לאינשי ולא משתכח

R'Se'orim replied: 'Are you, Sir, not his intimate friend? '<span class="x" onmousemove="('comment',' Lit., 'a bosom friend', cf. Sanh. III, 5. As a teacher of Torah, he is God's messenger himself. V. Mal. II, 6-7.');">³³</span> Said Raba: 'Since [my] mazzal<span class="x" onmousemove="('comment',' The guardian Angel.');">³⁴</span> has been delivered [to him], he takes no heed of me'. R'Se'orim then said to the dying: 'Do, Sir, show yourself to me [in a dream]'.

Jastrow