The Bible doesn't contradict itself. The intended meaning of the text is going to be the literal historical-grammatical one. Avoid allegorization and spiritualization of the Bible. Such techniques come from the Middle Ages, and are the province of such modern groups as Theosophy, Christian Science, and the New Age Movement. There is no place for such things in a truly rational approach to Scripture.
Scriptural passages are comprehensible as they are related to, and informed by others.
No, I worked harder than all of them - yet not I, but the grace of God that was with me. Salvation by grace has inevitable outward manifestations. Any work we do, the effort we make, is actually God working through us. God does the work, not us. Be imitators of God, therefore, as dearly loved children and live alife of love, just as Christ loved us and gave himself up for us as a fragrant offering and sacrifice to God.