The Zikr of Laa Ilaaha Illallah

It has been handed down to us that Abu Bakr al-Siddiq, may God be pleased with him, used to insert this phrase (la ilaha illa'Llah) into his conversation: he would utter a few words, say la ilaha illa'Llah, and then resume what he was saying. This pertains to the Station of Subsistence (baqa) which follows that of Extinction (fana).

From: The Zikr of Laa Ilaaha Illallah.