Majma al-Zawaid — Hadith 13068

Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates this as a marfu' hadith up to the Prophet (peace and blessings be upon him): He (peace and blessings be upon him) said: "Whoever humbles himself for Me like this" (the narrator said this while pointing with his palm toward the ground), "I raise him like this" (the narrator pointed with his palm toward the sky).
Al-Tabarani recorded it in al-Mu'jam al-Saghir. Its chain contains a narrator, al-Husayn bin al-Muthanna, and I do not know him. The rest of its narrators are the narrators of the Sahih.