Mishkat al-Masabih 390
Abu Salama reported Zaid b. Khalid al-Juhani as saying:
I heard God's messenger say, “Were it not that I would distress my people, I would order them to use the tooth-stick before every prayer, and I would postpone the evening prayer till a third of the night had passed.”
He said that Zaid b. Khalid used to attend the prayers in the mosque with his tooth-stick on his ear where a clerk carries a pen, and did not get up to pray without using it, after which he put it back in its place.

Tirmidhi transmitted it, and also Abu Dawud, but he did not mention, “I would postpone the evening prayer till a third of the night had passed.” Tirmidhi said that this is a hasan sahih tradition.
وَعَنْ أَبِي سَلَمَةَ عَنْ زَيْدِ بْنِ خَالِدٍ الْجُهَنِيّ قَالَ سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ: «لَوْلَا أَنْ أَشُقَّ عَلَى أُمَّتِي لَأَمَرْتُهُمْ بِالسِّوَاكِ عِنْدَ كُلِّ صَلَاةٍ وَلَأَخَّرْتُ صَلَاةَ الْعِشَاءِ إِلَى ثُلُثِ اللَّيْلِ» قَالَ فَكَانَ زَيْدُ بْنُ خَالِدٍ يَشْهَدُ الصَّلَوَاتِ فِي الْمَسْجِدِ وَسِوَاكُهُ عَلَى أُذُنِهِ مَوْضِعَ الْقَلَمِ مِنْ أُذُنِ الْكَاتِبِ لَا يَقُومُ إِلَى الصَّلَاةِ إِلَّا اسْتَنَّ ثُمَّ رَدَّهُ إِلَى مَوْضِعِهِ. رَوَاهُ التِّرْمِذِيُّ وَأَبُو دَاوُدَ إِلَّا أَنَّهُ لَمْ يَذْكُرْ: «وَلَأَخَّرْتُ صَلَاةَ الْعِشَاءِ إِلَى ثُلُثِ اللَّيْلِ» . وَقَالَ التِّرْمِذِيُّ: هَذَا حَدِيثٌ حسن صَحِيح