Then go into sajdah and say the following line one hundred times...
Then go into sajdah and say the following line one hundred times: أَسْتَخِيرُ اللهَ بِرَحْمَتِكَ وَأَسْتَقْدِرُ اللهَ فِي عَافِيَةٍ بِقُدْرَتِهِ. I ask the best from Allah by Your Mercy, and I seek the power and strength to perform this good work from Allah.
" Then, ask for your (legitimate) desires since in this is what is good for you in whatever happens." Istikhara in the Final Sajdah of Salat al‑Lail قَالَ الإِمَامُ الصَّادِقُ عَليهِ السَّلامْ: أَسْتَخِرِاللهَ فِي أَخِرِ رَكْعَةٍ مِنْ صَلاَةِ اللَّيْلِ وَأَنْتَ سَاجِدٌ مِائَةً مَرَّةِ وَ مَرَّةٍ تَقُولُ ((أَسْتَخِيرُ اللهَ بِرَحْمَتِهِ)).
al‑Imam al‑Sadiq (as) said: "In your final rakat of Salat al‑Lail, while you are in sajdah, ask Allah for the best by reciting the following one hundred and one times: أَسْتَخِيرُ اللهَ بِرَحْمَتِهِ `I seek the best from Allah by His mercy.
"[^3] Istikhara in the Final Sajdah of Nafilah of Salat al‑Fajr قَالَ الإِمَامُ الصَّادِقُ عَليهِ السَّلامْ: أَنْ يَسْتَخِيرَ اللهَ الرَّجُلُ لا فِي أَخِرِ سَجْدَةٍ مِنْ رَكْعَتيِ الْفَجْرِ مِائَة مَرّةٍ و مَرّةً تَحْمَدُ اللهَ وَ تُصِلَّي عَلَىَ النَّبِي وَآلِهِ ثُمَّ تَسْتَخِيرُ اللهَ خَمْسينَ مَرَّةً ثُمَّ تَحْمَدُ اللهَ وَ تُصَلِّي عَلَىَ النًبِيَّ وَ تَمِّمْ الْمِائةَ وَ الْوَاحِدَة.
Imam al‑Sadiq (as) said the following regarding asking Allah for the best: "In the final sajdah of the recommended prayers of Salat al‑Fair, one should seek the best from Allah by praising Allah and sending blessings on the Prophet and his family and then by asking Allah for the best fifty times followed by praising Allah and sending blessings on the Prophet one hundred and one times.