Al-Sadiq (as) said to one of his companions: Do not tell a secret to your friend, unless it would not harm you if an enemy were to find out, for a friend can become an enemy one day.
10 - وقال الصادق (عليه السلام) لبعض اصحابه: لا تطلع صديقك من سرك إلا على ما لو اطلع عليه عدوك لم يضرك، فإن الصديق قد يكون عدوا يوما ما (5).
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