He strengthened his heart
He encouraged him in a difficult time. "He strengthened his spirit" (originally: caused him to persist and entrench himself in his position).
("See all the wonders which I have put in your hand and do them before Pharaoh; and I will harden his heart, and he will not let the people go" — Exodus 4:21, said by the Lord to Moses about Pharaoh.)
Translation
Expression (Hebrew)
חִיזֵּק אֶת לִבּוֹ
Definition (Hebrew)
עוֹדֵד אוֹתוֹ בְּשָׁעָה קָשָׁה. "חִיזֵּק אֶת רוּחוֹ" (בַּמָּקוֹר: גָּרַם לוֹ לְהִתְעַקֵּשׁ וּלְהִתְבַּצֵּר בְּעֶמְדָּתוֹ).
("רְאֵה כָּל הַמֹּפְתִים אֲשֶׁר שַׂמְתִּי בְיָדֶךָ וַעֲשִׂיתָם לִפְנֵי פַרְעֹה וַאֲנִי אֲחַזֵּק אֶת לִבּוֹ וְלֹא יְשַׁלַּח אֶת הָעָם"- שְׁמוֹת ד כא, ה' לְמֹשֶׁה עַל פַּרְעֹה )