Majma al-Zawaid — Hadith 9414

Sayyiduna Mu'adh bin Anas (may Allah be pleased with him) narrates about the Prophet (peace and blessings be upon him) that a woman came to him and said: "O Messenger of Allah! My husband has gone out to fight. I used to follow him in prayer when he prayed, and to follow him in everything he did. So tell me of a deed that will bring me up to his deed until he returns." The Prophet (peace and blessings be upon him) said to the woman: "Are you able, until he returns, to keep standing in voluntary prayer without sitting, to keep fasting voluntary fasts without breaking them, and to keep remembering Allah without any pause?" The woman said: "O Messenger of Allah! I do not have the strength for that." The Prophet (peace and blessings be upon him) said: "By the One in whose Hand is my soul, even if you did have the strength for it, you would not reach even a tenth of his deed."
Ahmad and al-Tabarani recorded it. Its chain contains a narrator, Rishdin bin Sa'd, whom Ahmad declared thiqah (trustworthy) and a group declared da'if (weak).