Midrasz do Psalmów 34:8

R. Eliezer b. Jacob says: "Whoever wears Phylacteries upon his head, Phylacteries upon his hand, fringes on his cloak and has a Mezuzah on his door-post, these all will preserve him from sin, as it is said (Ecc. 4, 12) And a threefold cord is not quickly broken, and again there is another verse (Ps. 24, 8) The angel of the Lord encampeth round about them that fear the Lord."