Take note that Solomon says A mans heart deviseth his way.
I can devise much in my heart, make plans, determine to do such and such, but it in no way means that my devising will come to pass. There are many devices in a mans heart; nevertheless the counsel of the Lord, that shall stand. (Proverbs 19: 21) Though I devise, the Lord directs. Though I know not what the future holds, my goings are of the Lord.
An example of this comes after Moses delivered Israel from the bondage of Egypt. Bezaleel of the tribe of Judah emerged as the most skilled craftsman. With the help of others he made the tabernacle of the congregation, and the ark of the testimony, the mercy seat and all other things that would fill the tabernacle. One might look at Bezaleel and say that his becoming a skilled craftsman was of his own doing. Nevertheless, scripture says it was the Lord who directed his steps. I have filled him with the spirit of God, in wisdom, and in understanding, and in knowledge, and in all manner of workmanship, to devise cunning works, to work in gold, and in silver, and in brass, and in cutting of stones, to set them, and in carving of timber, to work in all manner of workmanship. (Exodus 31: 1-11)
Mans goings are of the Lord; how can a man then understand his own way? Who would trust their way to one who is unable to see afar off nor is he even capable of understanding his own way? Or who would find peace in relying on one whose council shall not stand? God in His word has ascribed to every man born in Adam these very same characteristics. (Gen. 6:5, Gen. 8:21, Proverbs 19: 21, Proverbs 20: 24) The believer knows these things and is in continual prayer that God will not remove his directing hand of grace.