John 10:16
“And other sheep I have, which are not of this fold: them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd.”
Not simply, “they ought to hear My voice,” not simply “they MAY hear My voice”, not “they will do so IF they are willing.”
There is no “if”, no “perhaps “, no uncertainty about it. “They shall hear My voice” is His own positive, unqualified, absolute promise. Here then, is where faith is to rest! Continue your quest, dear friend, after the “other sheep” of Christ’s. Be not discouraged because the “goats” heed not His voice as you preach the Gospel. Be faithful, be scriptural, be persevering, and Christ may use even you to be His mouthpiece in calling some of His lost sheep unto Himself.
“Therefore, my beloved brethren, be ye steadfast, unmovable, always abounding in the work of the Lord, forasmuch as ye know that your labor is not in vain in the Lord” (1 Corinthians 15:58).”
~ Arthur Pink, “The Sovereignty of God”