Musnad Ahmad 28:383

Bahz narrated to us, Shu'bah narrated to us, Ya'la ibn 'Ata informed me, from his father, who said: I think it is from Abdullah ibn 'Amr, he said—Shu'bah was uncertain—: A man stood up to the Messenger of Allah, peace and blessings of Allah be upon him, asking his permission for Jihad. He said: "Do you have parents?" He said: "Yes." He said: "My mother." He said: "Go and be dutiful to her." He said: So he went, walking between the mounts.