Fathers have had a hard time of it in recent decades. Those of us who are fathers (or married to one) know the struggle to work out what fathers are supposed to do (and whether they are very necessary at all).
Fathers do many things, but more importantly they just are. The thing about fathers is their character. And the thing their kids learn to appreciate (eventually, if not at all stages of life) is their love. Fathers can be notorious to their children for various strange behaviours or quaint preferences in dress or music, but children (of all ages) know when their father loves them.
In a way, loving children comes naturally at first. But like all loves fatherly love also has to be learnt and practised. Decisions to love and not to ignore have to be repeatedly affirmed. The father who can love best is the one who himself is loved - by his own father, by his wife, and most of all by his heavenly Father.
Being loved gives us the security to give love to others without having to use our love to gain theirs. The loved father becomes the loving father. Christian fathers know that they have a heavenly Father who loves them beyond all their needs.
Dale