Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "Shall I not guide you to something that will save you from your enemy and increase your provision? Supplicate to Allah Almighty by night and by day, for supplication is the weapon of the believer."
Abu Ya'la recorded it; its chain contains a narrator, Muhammad bin Abi Humayd, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الأدعية / 17199