Melting hearts, in Scripture, are consistently associated with discouragement and fear. Note a few examples:
“And he also that is valiant, whose heart is as the heart of a lion, shall utterly melt…” (II Sam. 17:10).
“Therefore shall all hands be faint, and every man’s heart shall melt” (Isa. 13:7).
“The heart melteth and the knees smite together…” (Nah. 2:10).
Christians, therefore, should not pray for melted hearts, as so many do. There are too many believers with melting hearts now! Indeed, men of God, down through the ages, have always found it a real task to keep the hearts of Christians from melting. Fear can easily become cowardice and cowardice, like courage, is extremely contagious. For this reason God explicitly instructed the military officers of Israel to announce to their armies:
“What man is there that is fearful and faint-hearted? let him go and return unto his house, lest his brethren’s heart faint as well as his heart” (Deut. 20:8).
If ever God’s people needed confidence and courage it is in the day of crisis — especially spiritual crisis — in which we live. Here Paul’s word to the Ephesian believers is appropriate:
“For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against [wicked spirits] in high places” (Eph. 6:12).
Thank God! While the opposition of our adversary during “this present evil age” calls for special courage and steadfastness of heart, God has made particular provision for us, for He has given us more light on His Word than was given those of former ages and we can meet the enemy with “the whole armor of God.” Moreover we have God’s Word through Paul, that battle-scarred warrior:
“God hath not given us the spirit of fear, but of power, and of love, and of a sound mind. Be not thou therefore ashamed of the testimony of our Lord, nor of me, His prisoner: but be thou partaker of the afflictions of the gospel according to the power of God” (II Tim. 1:7,8). source